Fenix TK40 Flashlight Review

I truly hate to venture anywhere near the land of hyperbole when reviewing a product – particularly for an audience as demanding and discerning as law enforcement officers. However, when you run across a tool as powerful as the Fenix TK40 it is nearly impossible to avoid seemingly cliché descriptions of its abilities. So when my coworkers jokingly began referring to this flashlight as the “day maker” or the “zombie killer,” I felt I could shamelessly pass along their informal evaluations of this incredibly powerful light.
I received the Fenix TK40 just over three weeks ago and carried the light on duty for three, 40+ hour tours on afternoons (1300 hours to 2300 hours). It served as my primary source of illumination for citizen contacts, traffic stops and calls for service after sunset. I carried the TK40 in the D-ring on my duty-belt – the one designed for my full-sized Maglight. During that same period of time, I also carried the TK40 on two search warrants as a member of my department’s SWAT Team. In a SWAT capacity, I toted the light on my person and utilized it for contraband searches and to cut through the smoke of flash-bangs after the initial entry.
The TK40 offers a maximum 630 Lumens generated by an LED light source. Frankly, the illumination quality of this flashlight is nothing short of incredible. In Turbo mode, the torch cuts through the darkness with a brilliant, white light that reaches distances well beyond any other flashlight I’ve ever worked with. I was able to illuminate the far reaches of a fenced backyard with this flashlight and effectively clear the entire visible portion of the yard from one position. On traffic stops, the TK40 washes the interior of the vehicle with light, enhancing both safety and your ability to detect contraband. Carrying the TK40 is akin to bringing your cruiser’s spotlight up to the driver’s window with you.
In Turbo mode, the TK40 offers approximately two hours of continuous operation before depleting the batteries. The bad news is that the light is powered by eight AA batteries and does not feature a recharging function. The good news is that the light also offers three additional light settings to increase battery life: low (150 hours @ 13 Lumens), mid (20 hours @ 93 Lumens) and high (6.8 hours @ 277 Lumens). Switching between the modes is a bit cumbersome at first, but familiarity develops quickly with use. Obviously a set of quality rechargeable AA batteries would be a solid investment for this light.
In addition to the four light output settings, the TK40 offers four secondary functions available at a double-click of the switch. Slow flash, fast flash, SOS and strobe. The SOS function hints at the flashlight’s origins as an outdoor-adventure tool. But the strobe is all business. I tested the strobe function on a number of participants: some willing, some unwilling. All parties agreed the strobe function was extremely disorienting and caused an immediate desire to look away or shield the eyes – both of which are desirable responses from subjects encountered in the dark. The strobe function is tied to the Turbo setting, meaning the combination of a blinding light source and the disorienting strobe may very well buy a few precious seconds for the officer.
Interestingly, after carrying the light for three weeks and using it in Turbo mode the entire time, I’m still on the original batteries with absolutely no fade in output.
I won’t lie: when I was first handed the light and advised of the price tag, I was extremely ginger with the TK40. That lasted about halfway through the first shift at which time I unceremoniously dropped it on the asphalt. After wincing at the sound of almost $160 hitting the deck, I picked up the light, clicked the switch and was pleasantly surprised to see I had done no damage. Unfortunately for the TK40, it was downhill from that point. During ensuing tours of duty, I dropped the flashlight at least a half-dozen times (mostly by accident), pounded on multiple doors and in general treated the light as though it were a standard-issue duty torch. Out of curiosity, I even submerged the light in my kitchen sink just to see if Fenix’s waterproof claims proved true. Through all of the abuse, the flashlight held strong. Even the finish withstood the abuse surprisingly well.
As with everything in this life, its virtually impossible to achieve absolute perfection. The downsides for the TK40 include its price, size and lack of a built-in recharging function. At $154.95, you will want to avoid leaving the TK40 on the table at Denny’s. But from what I can tell so far, the light is built to offer many years of reliable service and withstand the rigors of the street. Frankly, you pay for power and this flashlight is worth its price.
The TK40 is shorter than a D-cell Maglight, but just a thick. It is significantly lighter than other full-sized flashlights and thus easier to wield in combination with a handgun. Still, it would be dishonest to say it’s as convenient as a Stinger or similar sized torch. Again, this light is about power – you should expect to give up a small degree of handiness to get this kind of illumination. As mentioned earlier, a set of quality, rechargeable batteries would alleviate the TK40’s final shortcoming.
One last word of caution: it is a grotesque understatement to say this light is bright. In Turbo mode, it is blindingly bright. While cutting through a trailer park one night on the way back to my cruiser, I was using the TK40 in Turbo mode to light the way. I turned off the light and suddenly realized I had completely shut down my night vision. It was like stepping from a lit room into the pitch black. As with any piece of equipment, play with this light a bit before incorporating it into your arsenal.
Overall, this is a phenomenal piece of equipment that provides a degree of portable illumination second only to the spotlight on my fishing boat. If you’re looking for a light source to pierce even the deepest recess, consider the Fenix TK40.
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The “zombie killer.” I love it. Sounds like a good flashlight.
Nicely reviewed, Steve. I hope to see more of your work in the future. Uh, not at your day job.
Very well written commentary. You should think about writing professionally.
BTW…I think I’ll add this to my pesonal arsenal….and replace the namby pamby 180 Lumen has been light I carry now.
Nice review, I currently carry my good old Surefire 6P on duty and have done for the last 8 years. After reading about this bit of kit, it has been subtly mentioned to my wife as a nice present for my birthday next month. Looking forward to blinding some zombies with it.
The TK40 is going to be my next Flashlight, Fenix makes some great products and 630 Lumens is by far brighter (besides the headlights on my truck)than anything I currently own.
every thing you said is right about this light i bought one and it is fantastic i bought rechargeable batteries and every thing is working fine with me i just want to note one thing .
the battery holder inside the flash light makes sounds when ever the light is moving other than that the light is perfect and i love it and recommend it to any one and the light throws about 200-300 yards .
thanks.
Excellent review of the TK40 with which I can only agree.
Ahmad, with reference to your comment regarding the battery holder making a sound then I suspect this may be a fault and recommend taking up the matter with Fenix as I have never encountered this problem. If anything I would say that the torch is manufactured to a very high standard and even when shaken there is no noise or rattle.
Thankyou
Yeah I got one too, here is a video review of it that I done.
super bright led flashlight
There is a similar version the TK30 witch can use cr123a and 18500 li rechargeable batteries
How does this flashlight comapre to the Mag-lite 3d LED as far as the light color goes? I had a Mag-lite but returned it due to the annoying bluish tint. I’m looking for a “pure” white beam as opposed to a blue beam.
Thanks for this review. I was googling around for information on these lights for duty use, and your review was EXTREMELY helpful.
Ron – The MagLite is definitely more of a blue color, while the Fenix is much more white. I don’t know if it is “pure”, but definitely not the blue of the Magite LED.
CJ- Glad to hear this was helpful for you. We try to provide detailed, and accurate, assessments of gear.
Stay safe,
Richard
Great review. Looking at this or the new Tk41, which comes out soon and has a brighter LED
http://www.fenixoutfitters.com/fenix-tk41-pre-ordership-mid-april-304
Greg,
Thanks for the link to the TK41. We’ll try to get a sample to run some tests on.
-Richard
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