[Review] Nitecore TM20K 19x XP-L2

2 posts / 0 new
Last post
Mocarny's picture
Last seen: 16 hours 51 min ago
Joined: 05/10/2019 - 04:03
Posts: 419
Location: Poland
[Review] Nitecore TM20K 19x XP-L2

Nitecore TM20K 19x XP-L2

At the end there will be a summary for those who like only particulars. In each topic I will bold the key sentences, so it will be easier to notice what's the most important. Enjoy!






This flashlight was provided by Nitecore for the review. It does not affect my review, I always try to be as honest as possible.

Check the light from official Nitecore website: https://flashlight.nitecore.com/product/tm20k




Table of Contents:
- General parameters
- Package content
- Appearance, parameters
- UI, runtime and charging
- Waterproofness
- Light pattern, tint
- Beamshots
- Usage and my experiences
- Summary


General Parameters


Max Output: 20000 Lumens
Max Beam Distance: 290 m
Max Beam Intensity: 22200 cd
Max Runtime: 13h
Reflector: SMO (for 1x LED, no optic for 18x LED)
Battery: Rechargeable Li-ion (non-removable)
Special Modes: Strobe
Beam color: White light, cool tint
Length: 145.5 mm / 5.73 in
Head Size: 50 mm / 1.97 in
Weight: 422 g / 14.89 oz
Feature: STROBE READY, TurboReady
Activity: Search, Outdoor/Camping, Industrial



Package content


Package feels premium. Sturdy and nice looking box with nice graphics and main features



Inside there is a thick yellow paper with "Nitecore" on it, and other Nitecore flashlights from TM series



And a nice soft foam


With more squishy foam inside



And finally, the flashlight a holster.

Or should I say, the holster? Because it is made only for this flashlight, fitting perfectly. It also is well made, with two magnets to hold it closed, instead of velcro. I am a big fan of this solution, it doesn't wear out over time and you can sit all day long opening and closing it without it wearing out.


It has this plastic D-shaped...thing to attach it somewhere, I personally like to carry my flashlights like that


It also has this strange hole on the bottom


Seems to align perfectly with the center LED


Sooo...you could technically use it without even needing to take it out. But why?

It is no funny to use it that way, though. And you can say to someone that even your holster is brighter than his flashlight.


But be careful, not to accidentally click turbo button, because couple of seconds later you end up with melted and burning holster.

Yes, this thing can set stuff on fire, I tested it couple of times with a thin paper.




We also got a lanyard, a more sturdy one. Good, because I wouldn't want to risk dropping this flashlight because of poor quality piece of cord.

It can be attached with a little help of something stiff and pointy



But is it that well made? Let's find out:

Inside we have 6 plastic teeth to hold the cord, giving it very secure grip, it will definitely not loosen over time.\


But it's a shame it is that short, making it somewhat comfortable to carry in those two ways:




And here we have the flashlight, finally




So to sum up, this is what I got:


Wait, I almost forgot about this thing!


How nice is that!

You can place it next to your favorite flashlight. It even stands upright.

I'm not sure if it doesn't look even better without the flashlight.


Anyway, let's place it in my shoe for now




Appearance, parameters

Every basic thing you need to know about the flashlight


Size: for its brightness, I am genuinely impressed by the size

Like I saw many flashlights that size but outputting "only" around 2000 lumens.



Starting from the head:


  • Small and very nice stainless steel bezel. Much appreciated they haven't added a big aggressive tactical bezel

  • 19x XP-L2 LEDs, cool white, max output 20 000lm.

  • AR coated glass lens

  • Cooling fins are rather small

  • I like its design, because off small things like unique screws, or groove here and there

  • Very thick and well made clip, small dents on the sides for more comfortable grip



UI, runtime, heat dissipation and charging



I will try to explain it as easy and straightforward as possible:

You have 3 main modes: Lockout mode, Daily mode and Tactical mode, and couple of buttons



Lockout mode: flashlight is locked preventing it from accidentally turning on at 100% brightness, setting your sofa on fire, and burning down your whole house, while you barely escaped only having time to grab the rest of your flashlights and jumping through window.

What a relief we have the Lockout mode. And it is a 2 step lockout, not very easy to activate by accident.


Daily mode: this mode is designed to use in daytime. If you think the sun is not enough, you can use this Daily mode.

And it is the most basic mode, so you press the button, the flashlight shines until you press that button again.



Tactical mode: only for the bravest. Contains the most radical modes, with aggressive ramping and a scary sound.

No, wait... it is just a momentary mode, so shining only when button is pressed down.



Brightness is changed by this small side button




9600mAh seems like a lot of capacity. And it indeed is. You can use the flashlight for long hours before it runs out of power.


Low mode:

It sadly is not a straight line, but rather slowly falling to a 220 min point where it started to fail rapidly.



High mode:

Why I tested only 40 minutes? It is impractical and misleading to show "High brightness runtime" and saying it was shining for 200 min. What kind of runtime even is that? A generally-medium-but-starting-at-high runtime?

So here it is:

Heat dissipation

Heat dissipation is...is. Not very good, and couple-of-seconds-turbo affirm us in it. But don't tell me you expected long turbo time from that small and good heat dissipation fins lacking flashlight.


Built-in USB type C charging port. Charging up to 18W (12V and 1.5A)





I did not observe any flickering on the lowest mode.





Declared IP68

But only declared, and you know, it has many buttons, screws and other things, it might leak...

And it is expensive, so better not test it underwater. We can trust Nitecore in this.










Just kidding, let's drop it in the biggest jar I can find, fill it with water, turn on (which Nitecore advices not to do underwater) and leave it for 2 hours.


It did not leak, what a relief... Good job Nitecore. We really can trust you in this one. Wink


Light pattern, tint

19x Cree XP-L2 LEDs, cool white tint. 1 LED is placed in SMO reflector for a decent throw, other 18 are placed without any optics, resulting in a very wide and uniform beam.

White balance set to sunlight. As you can see, there is a bit of tint shift around the hotspot - it is not that visible in all modes but in ultralow, because all mule LEDs help to "hide" the tint shift caused by the center LED.



Difference between single LED and all LEDs combined is probably better visible when holding flashlight closer to the wall (or on beamshots, difference between ultralow (single LED) and low(all LEDs) is massive):






ISO200, t2s, f/3.5 sunlight white balance


General picture of what the forest looks like:




Nitecore TM20K:



The same pictures, but bigger:



More pictures, shining closely this time:

"Low" mode with 1050lm sound crazy! This also is the reason (next to its weight) why you should choose another flashlight for hiking - this one is simply too bright, I would use it for searching purposes.


3 years ago our dog got lost in the forest (probably someone stole it, but anyway) and we were looking for him for 5 days, day and night, and I was using Imalent DM70, because it has 21700 battery and good brightness. Today, I would definitely get this flashlight.

And we found our dog after those 5 tough days (someone decided to release it, probably seeing we are not giving up and driving to that forest every day, day and night)

His pictures are in the gallery below!




What about a small and unfair comparison? I know I know those are two completely different flashlights, in a very different price range. But:

20000 lumens vs 1500 lumens




Usage and my experiences

When it comes to holding it, I found those ways to be the easiest and the most practical:




I like the 2. way more, because changing modes with a palm is super easy and quick.



(for more "daily" use)


But please, don't change modes like that:

Grip is very unsecure, so you can drop it. And nobody wants that, right? RIGHT?




My other thoughts:

It is a bit heavy. Probably lighter than you expect a 20k lumens flashlight to be, but it "gets" heavier the more you hold it. I experienced it in one of my hikes when it started to feel heavy after 20min of holding it, and I needed to hold it on an outstretched hand.

Turbo working only couple of seconds was a big surprise for me, because I anticipated about half a minute, not couple of seconds. I mean, I understand it, what can they do with so small cooling fins and lightweight design (I know I said a while ago it is heavy - let me explain: heavy generally, as a flashlight for hikes and carrying it for a long time, lightweight as that bright flashlight).










Nitecore TM20K (Tiny Monster 20 000 lumens - what an informative name) is, you guessed it, a very bright, and relatively small flashlight. Powered by two 21700 cells, having a 9600mAh combined, can shine for long hours on lower modes. Batteries are not replaceable, though. While it is definitely a downside, our smartphones also have non-removable battery, and we still buy them. Those Li-Ion batteries (in smartphones) are guaranteed to have at least 80% of original capacity after 500 recharges, so roughly 2 years. Soo, if you somehow charge a flashlight with non-removable battery every day, it will still have 80% of its original capacity. Anyway, to output 20 000lm the TM20K uses 19x XP-L2 LEDs, one placed in SMO reflector for a decent throw, the rest just sits without optics (mule) to give a massive floodlight. UI is a bit complicated, because to operate the flashlight you need not one, but 3 buttons + slider. But I got used to it, and all modes are well designed with proper brightness stepping. If you need a very bright flashlight to use in every condition (thanks to its IP68 rating) then this is the flashlight for you.


+ IP68, doesn't leak in my test
+ 20 000lm, very bright


- A bit heavy, not suitable for long hikes
- Turbo lasts only couple of seconds


If you have any questions, put them below, thanks for sticking for a while Smile

If you struggle choosing your perfect headlamp, check my headlamp guide, I compared 15 most popular headlamps there: CLICK

roma58's picture
Last seen: 1 hour 16 min ago
Joined: 01/09/2016 - 19:38
Posts: 251
Location: italy

Thanks for the nice review.