The New Smoke Detector Hidden Camera with Wifi Remote Smart Phone and Internet Viewing

Written by Administrator. Posted in Product FAQs

Zone Shield Wi-Fi cameras allow easy remote viewing anywhere on the free EZ-See app. Event notifications alert you when the hidden camera has noticed activity at your home or office. Connect multiple cameras and view live streaming video from all devices on your tablet, smart phone or PC.

The New Smoke Detector Hidden Camera with Wifi Remote Smart Phone and Internet Viewing Its motion activated sensor springs to life faster than any other covert system so there’s no chance of missing an intruder. Because you never know when someone in your home will harm your family or your property the SleuthGear Xtreme Life is the right product to have if you don’t know when you’ll need it.
Up to 30 days of operation in standby mode on a single battery charge. Because it can work without wires, it can be placed anywhere and the PIR (heat sensor) conserves energy so that there is little worry of battery failure.  Its Just Like our Xtremelife Version, but Better!


You can buy the new Smoke Detector Hidden Camera with Wifi Internet Viewing Here


The future of DIY surveillance is Wi-Fi enabled covert cameras

Written by Administrator. Posted in Product FAQs

instide wifi outdoor camera

The future of DIY surveillance is Wi-Fi enabled covert cameras

Over the past few years, several Wi-Fi enabled overt cameras have entered the market, making DIY home and business surveillance simple and offering greater flexibility over connected homes and businesses without having to enter into long-term contracts and subscription-based services. In fact, we launched our own Wi-Fi home monitoring system in mid-2015.

While these cameras are a cost-effective way to monitor what’s happening while you’re away – and can serve as a powerful deterrent for anyone thinking about doing harm to people or property – the mere nature of the cameras being unconcealed may not offer you a complete picture of what’s going on while you’re at work, on vacation, or even while sleeping with night-owl teenagers coming and going.

This is where our exclusive, American designed SleuthGear® brand of surveillance cameras comes in. We admit, it has taken us awhile to make our Zone Shield and Xtreme Life lines Wi-Fi enabled, and for good reason. We’ve worked hard to find the right technology to offer you the quality you’ve come to expect of the SleuthGear® brand. We weren’t going to settle for substandard technology and inconsistent performance. That’s why we are especially excited about these line extensions. Our Wi-Fi hidden cameras offer true live view, require no Ethernet plugs and can perform up to 200 feet line of sight (LOS) from the router.


You can buy a Wifi Hidden Camera with Remote Smart Phone and Internet Viewing at

Looking To Buy a Night Vision Surveillance Camera Hidden Inside a Smoke Detector?

Written by Administrator. Posted in Product FAQs


If you are Looking To Buy a Night Vision Surveillance Camera Hidden Inside a Smoke Detector.  Look no Further!


Xtreme Life® Wi-Fi Night Vision Smoke Detector (Bottom View) on ceiling


Its motion activated sensor springs to life faster than any other covert system so there’s no chance of missing an intruder. Because you never know when someone in your home will harm your family or your property the SleuthGear Xtreme Life is the right product to have if you don’t know when you’ll need it.

Up to 30 days of operation in standby mode on a single battery charge. Because it can work without wires, it can be placed anywhere and the PIR (heat sensor) conserves energy so that there is little worry of battery failure.


Xtreme Life® Wi-Fi Night Vision Smoke Detector (Bottom View) top view

Buy a Night Vision Surveillance Camera Hidden Inside a Smoke Detector and See What you have been missing!





KJB Security Products Blog XtremeLife Product Line

Recently we introduced the SleuthGear Xtreme Life Hidden Camera product line which feature all-in-one hidden camera systems that can last for an entire year on a single battery charge. The response has been very exciting.…

KJB Security Products Debuts New SleuthGear Hidden

Both feature PIR heat sensors long life batteries and invisible infrared sensors for reliable surveillance and recording in almost total darkness. Like Recluse Xtreme Life is part of KJB’s exclusively designed SleuthGear family.…

This cool KJB Security SC7000 XtremeLife Artificial Rock

The SC7000 offers the convenience of a battery-powered camera KJB C7000 without the typical short battery-life constraints The KJB C7000 new XtremeLife camera KJB C7000 features the longest-life battery on the market.…

Xtremelife Rock Spy Camera Good Luck Finding It

In fact it can standby for up to a year on a single charge or take videos continuously for up to 20 hours. xtremelife rock camera. To maintain its stealthiness manufacturer KJB Security didn’t even point out where the pinhole is.…


Safety With Stun Guns – What You Need to Know After You Buy A Stun Gun Online

Written by Administrator. Posted in Product FAQs, Security Tips

Not Sure which Stun Gun is Right for you?  See Our Online Buyer’s Guide Here: Stun Gun Buying Guide

photo of Multi Action Stungun SM-Multi

Stun guns are small electrical devices that provide personal protection for those who carry them. They are non-lethal under most circumstances and are often carried by both men and women who want an extra measure of protection when they are alone.

In areas where stun guns are legal, there are generally no licensing requirements and no courses are offered in stun gun safety. This makes it important for each stun gun owner to take the time to familiarize themselves with the way stun guns work and how they should handle their stun gun for the most effective personal protection.

The first thing to do when a stun gun is purchased is to look over the device itself to become familiar with the important components. The button that activates the electric current should be located as well as the two contact probes that dispense this current. The probes are what will be held against an attacker in order to deliver the shock to them. Knowing exactly where they are will prevent the stun gun owner from accidentally shocking themselves when using it or testing it. Be sure to stay away from the contact probes, never touching them in order to avoid an accident.

Once these key parts are identified, the owner should make sure that the battery has enough power. Testing the stun gun periodically by holding it in the air and pushing the button will let the owner know whether the battery is still good. Having a stun gun with a dead battery can be dangerous for those who count on their stun guns for protection.

If a situation arises that calls for the use of the stun gun against an assailant, the stun gun must be close at hand in order to grab it quickly and use it. Plan out a place to keep it for just this type of emergency. Keeping it in a pocket or held onto the wrist with a strap will keep it close by. In a real emergency, there will be no time to dig through a bag to find the stun gun and prevent someone from committing violence.

Before discharging the electric current, make sure that your fingers or any other part of your body are not in contact with the current probes. The object is to shock the other person to allow the stun gun holder to get away. If both parties are shocked, the stun gun user may not get away safely.

The assailant holding on to the stun gun owner does not mean that the current will pass through both parties. Only direct contact with the probes will cause a shock. If the stun gun owners can’t shock the assailant without shocking themselves, they should wait for an opportune moment to do so instead of risking a shock to themselves. Some owners have scared away attackers simply by holding their stun guns in the air and activating the current. This may work in a situation where the attacker can’t be reached with the stun gun.


Are you more of a pepper spray person?  If so, see our complete article on how to handle and use pepper spray properly against attackers.



Stun Guns in the News:


Portland police seek to replace Taser stun guns with newer

The bureau whose officers came under federal scrutiny in 2012 for a pattern of unwarranted use of stun guns has used a Taser model X26 since 2005 but the company discontinued making them at the end of last year.…


Slay Enemies with a Cell Phone Stun Gun and Tactical

This cell phone-looking stun gun delivers 1,000,000 volts of lightning protection at the push of a button. Includes safety button extra-bright LED flashlight and case with belt clip. Requires three CR2 batteries included.…


Zone Shield C5500 AC Adaptor HD DVR Hidden Camera Review

Written by Administrator. Posted in Product FAQs


“Among all of the hidden cameras I’ve reviewed, the Zone Shield AC Adaptor HD DVR is definitely one of my favorites.” – Tony Tran



As you can see from the Video above, the new Zone Shield C5500 has a great picture.  What you may not know is that other versions of this camera have sold for more than $200 more!

Recently, Honest Reviews featured this product and had a lot to say.  Here is a snippet of the review by Tony Tran:


Zone Shield AC Adaptor HD DVR Hidden Camera Review


  • Video Quality:  4.5 Stars

  • Features:           4 Stars

  • Design:               4.5 Stars

  • Ease of Use:      5 Stars

  • Average: 4.5 Star Rating

Reviewed By 


GOOD Easy to use hidden camera disguised as a power adapter, High Definition Camera and no batteries are needed.

BAD Can only be used where an power outlet is available.

SUMMARY Although the Zone Shield AC Adaptor HD DVR hidden camera doesn’t have a ton of features, it has everything you need when it comes to a simple hidden camera for the right price.

The Zone Shield AC Adaptor HD DVR is a hidden camera disguised as a normal power adapter. All you need to do is insert the SD card into the “AC Adaptor” and plug it into an outlet to get started. It’s nicely designed and works well. I’ve been playing around with this little device for a couple of days and I’m loving it a lot.


Buy Zone Shield AC Adaptor Hidden Camera DVR C550


Buy the Zone Shield C5500 AC Adaptor HD DVR Hidden Camera Here

See the full product review for the C5500 here

Concealed Weapons Police Need to Know About – Places to Hide

Written by Administrator. Posted in Security Tips

How to search for and find concealed weapons – Places to Hide


Looking for concealed weapons means being thorough.  Here are some of the ways they may think they can fool you.


1. Jamaican Holster – Made from thin metal like a coat hanger


Jamaican Holster Image


Image of a Jamaican Holster Picture in Pants

2. The Headrest Compartment

The FBI is finding more and more of these compartments, where the back of the headrest flips open like a glove box.  Most handguns can fit inside.

Image of Headrest Compartment for Concealing Illegal Substances

3. Hidden Compartments

A kidnap victim pointed out this hidden compartment below in a 2000 Cadillac Seville STS.  The gun was found in a compartment that was revealed by pushing down on the tilt steering wheel adjuster.

Image of Hidden Compartment behind steering wheel tilt

Other hiding spots include:

Image of Video recorder gun safe


Image of a Video recorder gun safe open

Image Cut to Hide Gun


Image of Pepsi Machine Gun Storage

Image of Hollowed out car battery with hidden release mechanism.

3. Book Bombs

On Sept 10, 2001, Colombian National Police discovered this book.  It was to have been used to assassinate a prominent presidential candidate.  5 Lbs of plastic explosives were found inside that could be detonated via remote control or cell phone.

book bomb picture


4. Shot Gun Shell Booby Traps

During a drug investigation in Tillonsburg, England, 3 of these traps were found protecting a marijuana patch.   The barrels were directed at the ground, but could be aimed to injure or kill those who activated the trip wires.

image of shotgun booby trap


shotgun booby trap-2


This last example shows how staying vigilant not only gets more contraband off the streets, but also may save your life.


Do you have a story of your own you would like to share?  Post it in the comments below.  You just may help someone else who finds themselves in the same circumstance later on.


Don’t forget to check out our surveillance equipment for police interrogation rooms. Many of the custom built cameras can have audio added if the products are built for Law Enforcement.




Concealed Weapons Police Should Know About – Knives and Blades

Written by Administrator. Posted in Security Tips

Part II of our series on concealed weapons – Knives and Blades

Cat Hands:

Sold as self defense weapons:


Key Knives


  • Several on the market, sold at self defense stores, hardware stores, gas stations, and novelty stores
  • Very realistic looking and could be overlooked
  • Usually the blades are surgical steel and razor sharp
  • The “Swiss-Tech Utili-Key” has half straight and half serrated edge.


1 Inch Knife Blade:



A Standard Ballpoint pen casing hiding a 2 5/8″ surgical steel blade, serrated towards the handle. Modified from a Parker ballpoint pen and still writes as a pen.


A Letter Opener:


A Walking Cane Dagger:

Contains both a 5″ and 18″ blade. 


Baton Blade (Holds 2 Double Edged Swords)


Throwing Cards


Lighter Knife:

Several models, usually sold at tobacco shops

Works “stilletto style”

Polymer Knife – No Metal


 Calculator Knife:


 Lipstick Knife

Hair Brush Dagger – Poly-Resin Blade

Bike Seat Dagger – You may not know its there:


See our next article on Places to Hide Concealed Weapons.


If you are looking to buy concealed cameras click here



Concealed Weapons Police Should Know About – Homemade Guns

Written by Administrator. Posted in Security Tips

Everyday items can be modified to be used as weapons.

Some are devised by the bad guys.
ALWAYS remember ~ many criminals are smarter than we think. NEVER underestimate the ones who were “dumb enough to get caught.”

Why should we worry?

Homemade Guns

Cell Phone Guns

  • Several types have been found.
  • Several of this model have been confiscated in Holland recently, usually along with high volumes of explosives and narcotics.
  • Fires 4 .22 caliber ‘short’ rounds by pressing the keypad buttons…

Pictures of Cell Phone Guns


FlashLight Shotgun.

Flashlight Shotgun

The “Companion,” a 3 D-cell Mag-Lite flashlight converted into a shotgun capable of firing a .410 shotgun round. Manufactured by Ares Defense Systems. May be purchased on the Internet.Fully functional as a flashlight, it also works as a gun by pulling the safety pin, then pushing down on a spring-loaded firing pin. The projectile is discharged through the end cap of the flashlight. The company also sells a Mini-Mag-Lite (next slide). The items are covered by the National Firearms Act and possessing them requires you to have proper documentation of ownership.

Mini-Maglite Gun

  • 4” mini-mag flashlight (2 AA battery size)
  • Fires a single .380 round
  • Has an optional end cap that makes it look like a mini kubotan, vs. a flashlight

Image of Maglight gun


  • Used by fishermen and scuba divers to kill sharks and alligators.
  • Fires a single 38 caliber short Colt, .38 special or .357 magnum cartridge.
  • Considered to be a firearm when carried in a pocket or around the neck and used for other purposes.

Image of Bangstick

Folding Gun

  • A 5-shot .22 caliber pistol with a grip that folds over the barrel and cylinder
  • was concealed inside an eyeglass case when discovered
  • fits in pockets, hats, etc.

folding gun


World’s Smallest Gun

  • Fires .45 ACP, .357 Magnum, or .38 Special rounds
  • A break-down, single-shot, double action weapon made by Downsizer Corp.
  • 3 ¼” long, 2 ¼” tall, and .90” thick.
  • Imagine where this could be hidden…wallet, cigarette pack, palm, hats, etc., etc….

worlds smallest gun


Hunting Knife Guns

  • This is a 6-shot .22 caliber ‘pistol’
  • Cylinder and firing mechanisms are concealed inside the handle.
  • The handle breaks down and ‘ejects’ what becomes the grip and trigger
  • Fairly accurate for firing due to it’s overall length

Hunting Knife Gun


Pistol Pen

  • Just under 6” with a 2” barrel
  • “Stinger” model must be folded in half to fire, forms a handle to grip
  • .25 caliber, .22 LR, or .380ACP

Pistol Pen


Zip Guns

Some of the most commonly improvised firearms.

A handgun round is inserted snugly into a small diameter tube. That ‘loaded’ tube is then inserted into a larger pipe, which has an end cap with a piece of pointed metal inside it. When you slam the end cap back against a hard surface, the pointed metal strikes the primer of the round like a firing pin and discharges the weapon.

Zip Gun


 Bolt Gun

  • Fires a single .22 caliber Stinger. Pull back on spring-loaded hex head to fire.
  • 5/8″ diameter, 4″ long.

Bolt Gun


The Club Shotgun

  •  The handle end of The Club has been hollowed out to act as a barrel
  • When the lock end is pulled back, the interior metal cap (altered to act as a firing pin)
    is pulled away from the round
  • Fired by slamming the ends back together

The Club Shotgun


The Screwdriver Gun

The Screwdriver gun


The Pressure Gauge Weapon

  • Converted into .22 caliber pistol
  • Does not have plastic measuring device in the center
  • Last 1½ ” is a hardened steel barrel
  • To fire, remove threaded top, drop in cartridge. Pull the top and let go. Spring-loaded action, just like a zip gun.
  • ATF says possession is a federal crime, regardless of a person’s record.

Pressure gauge weapon


Next Up: Part 2 – Concealed Weapons Police Should Know About – Knives and Blades


You can purchase GPS and Police Hidden Surveillance Systems at


Snake Bites, Venom, and Stun Guns. Do Stunguns Prevent the Flow of Venom?

Written by Administrator. Posted in Security Tips

Active Stun Gun Image

There have been reports that venomous bites can be treated by purchasing a stun gun.  We’ve all seen movies where the hero burns a wound or tries to suck out poison from a wound and then moves on to get the bad guy.  Unfortunately, these things do not always work when tested in reality.  To answer this question, we have sourced a paragraph from the national institute of health, which reads:

“During the past 2 decades, articles suggesting that stun guns be utilized to treat venomous bites and stings have appeared in both the lay and medical press. Although never widely considered to be standard therapy for venomous bites and stings, stun guns are still considered to be a treatment option by some medical practitioners and outdoor enthusiasts. A Medline search was performed using these terms: venomous bites, venomous stings, snake bites, spider bites, electrical, stun gun, high voltage electricity, low amperage electricity, direct current, and shock therapy. Articles selected included laboratory-based isolated venom studies, animal studies, and case reports involving humans in which a stun gun or some other source of high voltage, low amperage direct current electric shocks were used to treat actual or simulated venomous bites or stings. We concluded that the use of stun guns or other sources of high voltage, low amperage direct current electric shocks to treat venomous bites and stings is not supported by the literature.”


There are numerous articles on this subject which can be seen here: Snake Bites, Venom, and Stun Guns.

Although buying stun guns can save your life, they are not the “panacea” of safety.  Awareness will always provide you with greater efficacy in protecting yourself and your loved ones.



Do Stun Guns Stimulate the Heart?

Written by Administrator. Posted in Product FAQs

Picture of Multi Functioning Stun Gun

It seems like from time to time we read about Tasers causing heart failure in certain people. However, people often confuse tasers with stun guns and although there are plenty of studies regarding the use of tasers (which is a brand of EMD weapons), stun guns fit into a much broader category.  If you are looking for our free online stun gun buying guide click here.

So the question remains. Do Electro Shock Weapons Stimulate the Heart?

The ability of an electrical discharge to stimulate the heart depends on the duration of the pulse, the voltage and the current density that reaches the heart. Stun guns deliver very short electrical pulses with minimal amount of current at high voltages. We discuss external stimulation of the heart by high voltage discharges and review studies that have evaluated the potential of stun guns to stimulate cardiac muscle. Despite theoretical analyses and animal studies which suggest that stun guns cannot and do not affect the heart, 3 independent investigators have shown cardiac stimulation by stun guns. Additional research studies involving people are needed to resolve the conflicting theoretical and experimental findings and to aid in the design of stun guns that are unable to stimulate the heart.

Stun guns are used to physically incapacitate a person by discharging controlled electrical energy into the body, thereby preventing effective muscular activity. Although the intention is to provide a safe means of subduing an uncooperative person, some studies have suggested that stun guns can stimulate cardiac muscle in addition to skeletal muscle, thus potentially promoting lethal cardiac arrhythmias. In this article, we review the scientific data about the direct effects of stun gun discharges on the heart during shock delivery. We discuss these issues in terms of electro-stimulation and correlate them with theoretical and experimental data in the literature. We discuss the principles of cardiac stimulation from internal and external stimulation and examine the evidence for and against cardiac stimulation by stun gun discharges.


Stun gun discharges

An older method of stun guns application, called “drive-stun,” functioned like a cattle prod, which required direct contact between the electrodes of the source and the target. Stun guns are manufactured by different manufacturers (e.g., Aegis Industries, Stinger Systems, Taser International) and they operate under the general principle of high-voltage discharge with short pulse durations. However, their operation and shock characteristics vary by manufacturer. For example, a recent model (X26, TASER International) feature 2 barbs attached to long copper wires that are rapidly propelled by compressed nitrogen and adhere to the target’s skin or clothes. This stun gun generates an initial 3 microsecond electric pulse, which produces an electrical arc that creates a low-impedance pathway for electricity to reach the body with or without skin contact.1 The initial pulse is followed by longer pulses (100 microseconds) that deliver electrical energy to the target’s body, which stimulates his or her nerves and skeletal muscles and results in incapacitation. This pattern is repeated at a frequency of 19 pulses per second. Incapacitation lasts for the duration of the discharge, which is typically 5 seconds but can be 15 seconds or longer if pressure on the trigger is maintained. The TASER X26 battery has the capacity to deliver up to 195 discharges of 5 seconds each,1 which corresponds to a duration of over 15 minutes. Other devices that have been studied include the M26 (TASER International) and the MK63 Trident (Aegis Industries), which is a stun baton. Each of these devices uses high frequency electrical pulses to incapacitate the target.


Method of stunning

Stunning can be attributed to 1 of 2 methods, which depend on the mode of application. In the “drive stun” method, the overwhelming factor is the creation of pain and hence compliance. The second method, in which electrodes are fired toward the target as projectiles, neuromuscular stimulation occurs over a larger area. In addition to pain, the device incapacitates the target by stimulating his or her motor nerves and muscles as well as sensory neurons. The duration and frequency of the pulses have been optimized to incapacitate the target, and different devices have varying effects depending on the frequency of stimulation and the shape of the electrical pulse.


Electrical stimulation of the heart

Since the early 1900s, various equations have been proposed to describe the relation between the current and pulse duration required for electro-stimulation of the heart. These formulas showed an inverse relation between the duration and the current of the stimulating pulse, which means that if the pulse duration is short, a higher current is required for stimulation.4

For an electrical pulse to stimulate the heart, it must depolarize the cardiac membrane below a certain level and the induced depolarization must be propagated throughout the heart. The duration and strength of the pulse must be sufficient to allow cell membranes to react and reach an excitation threshold above which activation is triggered. This activation produces a wave front resulting in mechanical contraction of the heart muscle. Shorter pulse durations require larger amounts of current or charge to stimulate the heart. Thus, one must consider whether a stun gun discharge, which is external to the heart, can deliver enough current to stimulate the heart. Below we discuss the external stimulation of the heart under other known circumstances and relate it to a typical electrical pulse generated by a stun gun.


Effect of external electrical discharges on the heart

The ability of external electrical discharges to alter the internal electrical activity of the heart (e.g., to induce ventricular fibrillation) has long been recognized. Depending on the method of delivery and the amount, timing and location of the electrical discharge, an external discharge can produce a beat when one is absent, induce fatal cardiac arrhythmias or restore a normal heart beat to a heart in arrhythmia.6 The use of external electrical discharges to influence the heart has resulted in the development of external pacemakers (e.g., Zoll stimulator) and defibrillator devices to treat ventricular fibrillation. However, these discharges are delivered under controlled conditions at rates that are physiologic or that are delivered during the safe part of the cardiac cycle. High voltage discharges commonly occur in various forms, from electrostatic discharge (most common) to electrocution or lightning strike (least common). Internal cardiac defibrillators also use high voltage pulses for terminating ventricular fibrillation. The relative values for voltage, current and energy for some common sources of high-voltage shocks, along with the most common type of stun gun in use, are shown below.



Evidence that stun guns cannot stimulate the heart

Despite the fact that stun guns are widely used and that their practical safety is under scrutiny, the majority of these analyses are theoretical in nature. These theoretical analyses suggest that stun guns cannot deliver the amount of energy required to stimulate the heart or cause ventricular fibrillation. Most theoretical studies base their arguments on the following principles: only a small portion (4%–10%) of the current that reaches the chest will affect the heart and the time constant of the cardiac cell membrane is much longer than the pulse duration generated by stun guns. According to the law of electrostimulation and given the electrical characteristics of stun gun pulses and cardiac cells, cardiac electrostimulation should not occur during a stun gun shock. These analyses support the claim that electrical pulses generated by stun guns are designed to specifically target skeletal muscle, which has a much smaller time constant (i.e., refractoriness) compared with cardiac cells.

Experimental studies that support the claim that stun guns do not stimulate the heart base their arguments on conservative device settings and experimental designs that often do not reflect a clinically relevant or “worst case” scenario. The studies by Lakkireddy and colleagues and McDaniel and colleagues, both involving swine, used a modified stun gun for which the output power could be controlled, allowing the authors to specify a safety margin for the device and to demonstrate that it could not induce ventricular fibrillation. McDaniel and colleagues used arterial blood pressure tracing, which showed no perturbations during discharge from the stun gun simulator However, intracardiac electrograms from the study by Lakkireddy and colleagues showed that the pulses did influence heart rate during shock delivery if the barbs were located such that they formed a vector crossing the heart. In contrast, the MK63 stun baton in the “drive stun” mode applied to the anterior thigh16 or thorax of Yucatan miniature pigs did not induce acute arrhythmias. The authors of both studies attributed their findings of a lack of cardiac stimulation to possible differences in electrode spacing, proprietary waveform or power generated by the device.

Other studies have been performed using healthy volunteers (police officers). Each volunteer received a single 5 second stun gun pulse to his or her back. This does not reflect the common scenario, in which multiple, prolonged shocks are delivered with the possibility of the barbs landing near the thorax. These studies recorded electrocardiogram findings before and after, but not during, the stun gun discharge. This, however, does not rule out the possibility of disturbances in the rhythm during the discharge owing to the artifacts in recorded electrocardiograms during the discharge. These limitations prevented the researchers from observing transient changes in heart rhythm during discharges. The immediate recordings after the discharges18 showed shortening and lengthening of QT complexes without assigning any significance to these changes.

Stun gun discharges have been recorded in the field and there have been no claims of deaths medically attributed to these discharges. These recordings were made immediately after, but not during, the discharge. Although this does not affect the claim of no related deaths, these studies cannot verify whether the heart was stimulated during discharge. In cases of recorded deaths, the mode of death had never been established, though a state of “excited delirium” has been reported. However, excited delirium has not been listed as a cause of sudden cardiac death in the arrhythmia literature.

Evidence that stun guns can stimulate the heart

Deaths have occurred shortly after stun gun discharges. However, association alone does not prove causality. The possible mechanisms of short-term or immediate-term cardiac effects relate to the stimulation of the heart or induction of ventricular fibrillation. Stimulation of the heart is a separate issue compared with induction of arrhythmia, as stimulation may happen only during discharge and may not be evident even immediately following the discharge. In contrast, induction of arrhythmia may relate to stimulation of the heart because, depending on pre-existing defects (e.g., a previous heart attack, drug intoxication), each person’s heart may have a different susceptibility to life-threatening arrhythmia during stimulation. Podgorski and colleagues found that the direct application of an older version of a stun gun to a pig heart, which was exposed but covered by a towel, produced stimulation of the heart.

Because the theory of electrical stimulation suggests that stun gun discharges should not stimulate the heart, we tested the hypothesis using a closed-chest in vivo animal model. A unique feature of our study was that real stun guns were used and operated by qualified law enforcement personnel, which simulated real-world conditions. Two different models (TASER X26 and M26) that deliver different pulse waveforms were used on an anesthetized pig. Recording the electrical activity of the heart is challenging, because the acquisition system is usually completely saturated by the electromagnetic interference generated by the stun gun discharge. However, we found that the pig’s arterial blood pressure was occasionally abruptly lost during stimulation. To further verify that this blood pressure modulation was not a recording artifact, we opened the artery to air and found that the pumping of blood stopped during the discharge of the stun gun. This made us suspicious that either an arrhythmia was being induced or the heart was being stimulated so rapidly that it was not capable of producing pulsatile pressure. To test this, we shielded our mapping system and recorded the electrical activity during discharge.

We studied a total of 150 discharges in 6 pigs. Of these, 74 of these discharges resulted in stimulation of the myocardium, as documented electrical capture (a provoked response in the myocardium) (mean ventricular rate during stimulation and capture, 324 [standard error 66] beats/min) (Figure 1). Of the 94 discharges across the heart, 74 stimulated the myocardium. We took care to ensure that the gun barbs did not pierce deep into the tissue. We also placed the barbs such that they were oriented across the heart, simulating the worst case scenario of creating a current vector that directly passes through the heart. If these barbs were placed away from the chest and across the abdomen, none of the 56 discharges across the abdomen stimulated the heart (Figure 2), suggesting that the location of the barbs had a crucial influence on stimulating the heart. We also observed that the waveform (pulse shape) produced by the device affected stimulation, because when we used a different model of the stun gun (TASER M26), we observed a lower incidence of cardiac stimulation.


Figure 1:

Stun Gun Cardiac Stimulation

Cardiac stimulation and hypotension from a stun gun discharge. Note the corruption of the surface electrocardiographic leads in panel B and the electrical activity of the intracardiac electrograms. After stun gun discharge, a spontaneous and immediate return of regular sinus rhythm and blood pressure occurs (panel C). Panel D and E show magnified intracardiac electrograms of similar duration. It is evident in panel E that the rate is much faster and the rhythm is wider than in panel D. The morphology of the tachycardia in panel E is wider than the morphology in panel D. There is a constant stun gun stimulus artifact to electrogram duration as illustrated in panel E, with every fourth stun gun discharge resulting in stimulation of the heart. Note the loss of blood pressure during the stimulation and the recovery of blood pressure once the discharge is completed. Reproduced with permission from Elsevier (Nanthakumar et al24). Note: CS = coronary sinus, RV = right ventricular, BP = blood pressure.

Figure 2:

A typical episode of a stun gun shock across the abdomen (nonthoracic vector) that does not result in stimulation of the myocardium. The surface electrocardiogram lead 1, intracardiac electrograms from the coronary sinus, the right ventricle apex and blood pressure in the descending aorta are shown. Panel A illustrates the regular rhythm before the discharge, which is very similar to the rhythm and rate in panel C. The intracardiac electrograms, as illustrated in panels D and E, do not show any significant change in rate morphology and are not phase-locked (no temporal relation between stimuli and the electrogram) with the stun gun discharge. Note also the lack of perturbation of blood pressure during the discharge. Reproduced with permission from Elsevier (Nanthakumar et al24). Note: CS = coronary sinus, RV = right ventricular, BP = blood pressure.


In addition, we simulated an excited state infusing pigs with epinephrine, which renders the myocardium more excitable and prone to arrhythmias. Of 16 discharges, there were 13 episodes of myocardial stimulation, of which 1 induced ventricular fibrillation and 1 caused ventricular tachycardia. In contrast, another study, which simulated an excited stated by infusing cocaine into pigs, did not report induction of ventricular fibrillation during discharge. The main conclusions of this study was that stun gun use in the presence of cocaine does not increase the chance of arrhythmia. However, this study used a waveform simulator, not an actual stun gun, and although ventricular fibrillation was not induced, there was stimulation of the heart.

Three different studies involving pigs, 1 of which was performed by us, have shown that a stun gun discharge can stimulate the heart. In particular, 1 studyreported the deaths of 2 animals caused by ventricular fibrillation immediately after the stun gun discharge. This study also reported severe metabolic and respiratory acidosis caused by discharge. This suggests that sufficient current density was produced by the stun gun to stimulate the heart, which according to theory should not occur. A potential explanation of why, despite the theory, stimulation was observed is that there were metallic objects (e.g., catheter or pacemaker leads) inside the heart, which probably carried currents induced by the electromagnetic interference generated during the shock. One could argue that these currents could instead be the primary source of heart stimulation. Because capture could only be observed using intracardiac electrograms, this remains speculative. The fact that in our study we did not observe capture when the stun gun shocks were administered away from the chest suggests that the dart locations play a more important role in stimulation than the presence of metallic objects in the heart. In addition, in our study, we removed all electrical catheters from the heart and still observed the cessation of arterial pumping during discharge. We also confirmed that even without catheters in the heart, stun gun discharges on the chest can stimulate the heart and, at the least, can result in a loss of blood pressure during discharge.

Indeed, a human’s chest is different from that of a pig, and there may be differences in electrophysiology between human and pig hearts. One should be prudent in extrapolating data from animals to humans because of this fact. The corollary, though, is that most of the basic mechanistic concepts in cardiac fibrillation and defibrillation are derived from animal studies, not humans. In addition, the safety margins for energy of stun gun discharge established by manufacturers were derived from animal models.

Researchers from San Francisco recently published the case of a patient with a pacemaker who received a stun gun shock. They observed that discharges from the stun gun provoked a response in the myocardium (Figure 3). It is unknown if this would have occurred without the presence of pacemaker wires, although without these wires, verifying the presence of cardiac capture would not have been possible. In addition, John Webster’s research group reported in a conference abstract that stun gun discharges can stimulate the heart. Although published theoretical analyses about stun gun safety have scientific merit, we should be aware that theories are only as good as the assumptions and conditions defined based on available data or knowledge.

Magnified summed intracardiac electrograms from a patient’s internal pacemaker log during stun gun discharge. Cardiac capture is shown by the high-rate ventricular sensing (cycle length 203–289 milliseconds); the cyclic, low-frequency modulation of high-frequency noise (stun gun pulses) during ventricular sensing; a single, long ventricular interval (648 milliseconds) after the energy stops; and postdischarge resumption of atrial and ventricular sensing at a rate similar to predischarge cardiac rate. The high-frequency pulses (15 pps, 66 milliseconds) are labelled on the tracing. The intracardiac electrograms from the last sensed ventricular event during stun gun application are superimposed on each prior ventricular sensed event, showing that the disruption of the high-frequency stun gun signal is consistent with modulation of the signal by a repeating R wave with morphology different than the intrinsic R wave (right side of the image). Reproduced with permission from Blackwell


Explaining the discrepancies between theory and observation

Why have 3 independent groups of investigators reported in peer-reviewed journals that cardiac stimulation can occur when the theory says it cannot happen? Theoretical safety calculations may not hold true if the theory used to calculate the membrane time constant using external pacing parameters (i.e., with large pads that do not break the skin barrier, without rapid stimulation at high voltage) does not apply to stun gun stimulation across the chest wall. Although the membrane constant is usually considered an intrinsic property of cardiac muscle, various studies have measured time constants during human trans-chest pacing from 0.5 milliseconds to 1.1 milliseconds. However, another study with direct pacing on dog myocardium reported an average value of 2.4 milliseconds, suggesting that the time constant is actually a characteristic of not only the cell membrane but also the stimulator, and the size and the position of the electrode used. This suggests a large variability over the population; thus, an identical pulse with a specific duration and strength could have different stimulation effects on different people.

Over the last century, various studies have been performed on the strength–duration relation of electric impulses and their effect on cardiac stimulation. From some of these studies, it is evident that the assumptions made about membrane time constants and contact electrode sizes strongly influence the outcome. Typically, electrodes in contact within the myocardium may stimulate with 50 milliamperes when the current is injected over a period of 50 microseconds. However, shorter pulse durations would require a larger amount of current to stimulate the heart. There is a possibility of inducing a lethal cardiac arrhythmias when factors (e.g., strength, duration and frequency of the electric pulses; membrane time constant; contact impedance; and timing of electrical discharge) favour triggering the heart during a vulnerable period of the cardiac cycle.


Knowledge gaps

Although there have been deaths reported following stun gun discharges, this appears to be rare. In addition, some animal studies suggest that stun gun shocks may have cardiovascular effects. Whether the reported deaths were related to the external shocks is unknown. It is also unknown whether cardiac stimulation occurs only during discharge. The observational studies involving human volunteers thus far could be considered phase I studies because they relate mainly to tolerability and do not prove the safety of the devices. It is very important that tolerability should not be misconstrued as safety. The largest knowledge gap is the lack of appropriate studies involving humans to establish the safety margins for stun gun shock energies when the vector of discharge is across the heart.

The effects of potential modifying factors such as sex, body mass, cardiac and noncardiac diseases, alcohol, medications and psychotropic drugs also need to be evaluated. It is evident that psychotropic drugs such as cocaine heighten the sympathetic state in animal studies. The effect of these drugs and their influence on human autonomic physiology during stun gun discharges is an important aspect that needs urgent evaluation.



Despite many studies suggesting that stun guns do not affect the heart, the evidence and studies presented in this review suggest that, in some circumstances, stun guns may stimulate the heart while discharges are being applied. However, there is no conclusive evidence to show whether stun gun stimulation (under certain electrophysiological conditions) can result in cardiac arrhythmias late after stun gun discharge. In our view, it is inappropriate to conclude that stun gun discharges cannot lead to adverse cardiac consequences in all real world settings.

We believe that the findings that stun gun discharges are able, under specific circumstances, to stimulate the heart should be taken into account in future studies involving people. Whether stun guns can stimulate the heart can only be established if one can record electrical activity in the heart during a discharge, especially when the vector of discharge is directed across the heart. Additional research studies involving people will help to resolve the conflicting theoretical and experimental findings, and they could lead to the design of devices with electrical pulses that cannot stimulate the heart.




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