Klarus G15 Flashlight Review – Better than other 21700 lights?

Klarus has released the Klarus G15 flashlight, a new 21700 light.  This is a floody Cree XHP70.2 light, claiming 4000 lumens, and uses a single 21700 cell!  Read on to see how it test, and if it’s better than the competition!

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Official Specs and Features

Here’s a link to the official product page.

Versions of the Klarus G15 21700 Flashlight

There is just one version of the Klarus G15.

Price

These are listed at $89.95 currently.

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Short Review

There are a number of things to really love about the Klarus G15 21700 flashlight and a one or two that could improve.  First, this light unlike many similar lights does not use proprietary or customized 21700.  That is a massive plus.  The build quality is good, and the output is very nicely thermally managed.  However, this is a cool white light and has a huge stepdown from the 4000-lumen claim (which it does reach, initially).

Long Review

The Big Table

Klarus G15 Flashlight
Emitter:	Cree XHP70.2 (6500K)
Price in USD at publication time:	$89.95
Cell:	1×21700
Turbo Runtime	High Runtime
LVP?
Switch Type:	E-Switch
Quiescent Current (mA):	0.16
On-Board Charging?	Yes
Charge Port Type:	Micro-USB
Chargetime
Power off Charge Port	With Cell: Lowest 3 modes. Without Cell: No.
Claimed Lumens (lm)	4000
Measured Lumens (at 30s)	2000 (50% of claim)^
Candela per Lumen	2.6
Claimed Throw (m)	188
Candela (Calculated) in cd (at 30s)	423lux @ 3.716m = 5841cd
Throw (Calculated) (m)	152.9 (81.3% of claim)^
All my Klarus reviews!

^ Measurement disclaimer:  Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.

What’s Included

• Klarus G15 Flashlight
• Klarus 5000mAh 21700
• Charge cable (USB to micro-USB)
• Lanyard
• Carry pouch
• Spare o-ring
• Manual

Package and Manual

In the photo above, the box is a little bit open.

Build Quality and Disassembly

The build quality of the Klarus G15 is fine.  It feels like a sturdy light.

The bezel sits over the edge of the flashlight and seems to screw in.

The body has what seems to be the “new standard” of finish.  Not really knurling, but more of a grip pattern.

The tail/cell tube is one piece.  The light as a whole just has two main parts. Head and tell (cell tube).

The head has some texture reminiscent of cooling fins, which probably do help with cooling.

A thing that surprised me about this light is that the threads are not anodized.  This may affect how you see the “quality” of this light, but to me, it does cheapen it just a little bit.  The threads work just fine, but bare aluminum on bare aluminum has a “nails on the chalkboard” feel for me that I just don’t enjoy.  Of course, overall this probably provides better electrical contact!

The head has a nice thick double spring.  And note that “retaining ring” (which isn’t really, or at least not in a standard way) is held down by two Philips screws.

The tail end has a nice beefy spring, too.

Size and Comps

Officially 120.6mm long, and 27.6mm in diameter (at the head), and 25.3mm in diameter at the tail.

If the flashlight will headstand, I’ll show it here (usually the third photo).  If the flashlight will tailstand, I’ll show that here, too (usually the fourth photo).

Here’s the test light with the venerable Convoy S2+.  Mine’s a custom “baked” edition Nichia 219b triple.  A very nice 18650 light.

And here’s the light beside my custom engraved TorchLAB BOSS 35, an 18350 light.  I reviewed the aluminum version of that light in both 35 and 70 formats.

Retention and Carry

The Klarus G15 ships with a friction fit pocket clip installed.  The clip is pleasantly “deep carry” and feels quite snug.

There’s a groove for the clip only on the tail of the light, so bezel down is the only carry option.

The lanyard is intended to attach on the tailcap through this hole, but could also attach to the pocket clip if desired.

There is no pouch included and there is no magnet inside.

Power and Runtime

The Klarus G15 is powered by a single lithium-ion cell.  Klarus includes an appropriate cell – it’s a button top 21700.  Unlike many other lights in this series (notably by Thrunite and Olight), this 21700 is not proprietary, and other standard 21700 cells will work.  But read more on that later….

The button on this cell is short and fat.

The cell goes into the light in the normal orientation, which is with the positive terminal toward the head.

Here are a couple of runtimes.  Regarding the cell – this light does actually pump out 4000 lumens.  That’s a massive bit of output.  You wouldn’t really expect it to hold that for very long.  But the output is extremely short at that level and steps down into the 2000 range very quickly.  So my 30-second reading is after the stepdown, and as a result, this light reads “2000 lumens.”  Initial output draws over 12A from the single cell, so while I did say any cell will work in the light, probably not all cells can handle that level of current output.

This light also has some fairly active thermal management.  After the initial stepdown, the output drops in a seeming temperature-based pattern, then the output slowly increases again, up to the “2000” lumen range.  This seems to go on until the cell voltage drops, and the light eventually steps down to very low.

High is regulated in much the same way, but the lumen band is narrower.  Due to the light not stepping down so hard, this mode actually reads higher at 30s than Turbo.

The indicating switch gives a short indication of cell voltage, as follows:

Green: 70%-100% power remaining
Orange: 30%-70% power remaining
Red: <30% power remaining
Red Flashing: <10% power remaining

The Klarus G15 also has built-in charging, by way of a micro-USB port in the head.  There’s a press-in cover, which fits more specifically that most.

I tried and tried to get a charge cycle logged, but something about this and my charge setup did not work.  I did record it on an alternate device, and I can report that charging is at around 2A.

Modes and Currents

Mode	Mode Claimed Output (lm)	Claimed Runtime	Measured Lumens	Tailcap Amps
Turbo	4000	1.2h	2000	12.36
High	2000	1.5h	2213	4.20
Medium	500	6h	557	0.81
Low	100	28h	116	0.14
Moonlight	1	200h	~	~

Over twelve amps on turbo!!

Pulse Width Modulation

There isn’t any PWM, but the middle three mods have an unusual wavy pattern on the scope, but it’s not PWM, and not noticeable.

For reference, here’s a baseline shot, with all the room lights off and almost nothing hitting the sensor.  Also, here’s the light with the worst PWM I could find.  I’m adding multiple timescales, so it’ll be easier to compare to the test light.  Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms.  5ms.  2ms.  1ms.  0.5ms.  0.2ms.  In a display faster than 0.2ms or so, the on/off cycle is more than one screen, so it’d just (very incorrectly) look like a flat line.  I wrote more about this Ultrafire WF-602C flashlight and explained a little about PWM too.

User Interface and Operation

The G15 has a single switch.  It’s an indicating e-switch, with a softcover.  The switch is positively clicky.

The indicating is unusual – most often the indicator will be a dot in the center, which shows the indication.  In this case, the indicating ring is on the outside edge of the switch cover, which I have to say, is very cool.  Below, the switch is indicating in green.

Here’s a UI table!

State	Action	Result
Off	Click	On (memory, excluding low and turbo)
Off	Hold	Moonlight
On	Hold	Mode advance (LMH only)
On	Click	Off
Any	Double click	Turbo
Any	Triple click	Strobe
Strobe	Triple click	Beacon
Beacon	Triple Click	SOS
Off	Hold 5s	Lockout (Two flashes of main to indicate) (further clicks blink 3x red to indicate lockout)
Lockout	Click 3x	Unlock (Two flashes of main to indicate)

LED and Beam

The emitter in the Klarus G15 is a Cree XHP70.2, with a medium depth orange peel reflector.  The color temperature of the emitter of choice is 6500K, which is cool white.

These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure.

Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)

I keep the test flashlight on the left, and the BLF-348 reference flashlight on the right.

I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!

Conclusion on the Klarus G15 21700 Flashlight

What I like

• Complete package
• Initial output is extremely bright!
• Regulated and high output in the High mode
• Uses a regular 21700 cell
• Regular 21700 cell is included
• Good UI with easy access to Moonlight and Turbo

What I don’t like

• The price is a little high, at $89.95
• Cool white emitter.

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Notes

• This light was provided by Klarus for review. I was not paid to write this review.
• For flashlight-related patches, stickers, and gear, head over to PhotonPhreaks.com!
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