Tactical Illumination Sources

An illumination source is key for success on a variety of missions, whether it’s down range, signalling traffic, looking inside a parked vehicle, conducting a search, even locating the spare change that has fallen under your car seat. No matter your occupation, a quality standalone flashlight is absolutely critical. In the case of Law Enforcement, it is arguably the most used piece of kit after your radio. However, many of us have begun to rely on weapon based illumination tools, when we really require two illumination sources, one as a key component of a weapon system (pistol or carbine) and one as a stand-alone illumination source.

A weapon-mounted light should never be considered an illumination tool, it is a feature of your given weapon system (sidearm, carbine etc.) You should only point the light at something you are willing to destroy; it is one of the basic firearms safety rules. The truth is: there are instances across law enforcement where a negligent discharge occurred while an officer under stress attempted to utilize his weapon mounted light as an illumination tool.

The important thing to remember about weapon mounted illumination tools is they were developed for special operations forces (the exact unit is up for debate, the US Navy SEALS and a few other units have weighed in.)  That’s right, the weapon mounted flashlight was designed with the general concept that “if the light is on it, it’s a target.” Naturally when the device spilled into the civilian market there was the usual training debate. However, many police officers received minimal training on when to employ a standalone versus weapon mounted illumination source. The critical view of the weapon light as part of the weapon system was largely ignored. Police officers stopped carrying illumination tools on their duty belts, as they now carried pistols with a light or even light-laser unit attached. This situation is further echoed by civilian citizens, like police officers, a civilian shooter may well need to illuminate something that they do not wish to destroy.


Look for cool white, LED based beams with a noticeable and large hot spot when selecting a light for duty use.


While the military will utilize night vision, IR technology, and other tools to effectively conduct missions in the dark, there are still lessons to be learned in carrying an illumination source other than your headlamp and weapon light, you simply do not know when you will be required to conduct a mission where such a tool will be required, examples include: intelligence collection, vehicle searches, and even making your way to the latrine. While the argument has been made that adding something like a flashlight to an already heavy LBE is a poor choice due to the added weight the benefits may well outweigh the negatives.

So, what should you look for in an illumination source?  A tactical illumination source must be light weight, durable and have a long run time. To this end, modern LEDs are the only choice. LEDs consume far less energy, equating to better battery life. More importantly, LEDs will not shatter if dropped, or from a general impact to the carrying platform.


A dual switch tail cap like the one on the TK16 is ideal for rapid manipulation of the light.

Many tactical lights have a strobe function. Feelings on the application of a strobe are mixed, however there is considerable scientific grounding. When the human eye is hit with a strobe the brain produces an effect known as flicker vertigo. Symptoms of flicker vertigo include nausea and anxiety. For sensitive individuals, a strobe can induce muscle rigidity, seizures (epilepsy) and loss of motor function. A strobe setting on your personal illumination source provides you with a non-lethal tool, and the truth is whether for law enforcement, military application or personal defence having less lethal or non-lethal options is always a serious bonus.

While discussing lethality, it is necessary to consider the ability to operate your illumination source if you are injured. Pressure caps, and other switch designs should be large and easy to operate even under gross motor skills. If you wish to test your ability to manipulate a piece of equipment with gross motor skills there are a couple of options. First, conduct an all-out sprint or other form of intense exercise and then attempt to utilize the equipment. Second, place your hands in ice water for 3-5 minutes until they are completely numbed, then conduct your drill or equipment test. Finally, spread dish soap on your hands (dish soap is much like blood on a surface) and attempt your drill.

An Example

While there are tens of thousands of reviews on tactical flashlights across the web, few address the aforementioned points regarding their application into your duty systems. When you shop for a tactical illumination source you need to consider each of these design components, not just what is the most “high speed” (can an illumination source be high speed?) Let’s review the Fenix TK16 (our current duty carry light) from each of the key data points.


The TK16 features a durable dual layer body, and an overall excellent build quality. Notable features of the design include a dual switch tail cap (on/off and strobe) and anti-roll dimples. Most importantly the TK16 utilizes quality LEDs that produce a cool white beam. The beam throw is excellent, and provides a large noticeable hot spot. When looking at the beam of flashlight, you want to see an intense hotspot with a softer beam throw edge, enabling your peripheral vision to function effectively. The greater the field of view you are able to produce outside of the hot spot the greater your chances of detecting a threat in a high-risk situation.

Manipulating the TK 16 across it’s brightness modes (there are four) is a simple. Once the light is on, use the strobe button on the tail cap to cycle through the various brightness settings. Gunslinger Research found this design to be preferable to the more common rotary switches.

Battery Life

Featuring a reverse polarity function and taking standard CR123As (including flat tops) the TK16 exhibits exceptional battery life. However, a flaw in the design is that there is no rechargeable version available. This being said, we found that the TK16 functioned well with rechargeable CR123As. Furthermore, the TK16 beam does not artifact and exhibits excellent intensity even when using rechargeable batteries.

Weapon System Applicability

Should you wish to weapon mount the TK16, a pressure switch and mount is available in a combo pack with the TK16 itself and a standard nylon belt pouch. The weapon mount and switch are of equal build quality to the unit itself and mounted easily to all standard pica tinny rails. However, the TK16 is far too large to be used as a pistol weapon light. While the adaptability would be nice, it is hard to view this is a con as the TK16 is not marketed as pistol mountable.

Final thoughts

The TK16 is a surprising balance of price and tactical features and is an excellent example of what to look for in a tactical illumination source.  The price is low enough that you can purchase one as a stand-alone flashlight, and a second as weapon-mounted light for less money than a light from other manufacturers with similar features. While other manufacturers are notable for being battle proven, the TK16 has been carried by Gunslinger Research collaborators across the globe in hazardous environments and has not failed. Tested in Africa, South America, and even the Canadian Arctic the TK16 performed flawlessly and was not impacted by inclement weather.


Categories: Shooting Performance

3 replies

  1. Great article. I will weigh in more tomorrow morning, but this is spot on. When we started to allow the officers to carry a weapon mounted light, we had to have quite a discussion on exactly that. It is a weapon with a light attached.

    Incredibly advantageous in some circumstances, but also misused in others. Your primary illumination device in most, not all, circumstances will be your carry light. And you had better have practiced with your firearm and your carry light. You won’t just perform because it is nice and expensive gear. You will perform because you have at least practiced with it some.

    Great article . Stay safe everyone.


  1. Practical Pistol Enhancements for the Law Enforcement Landscape – Gunslinger Research

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