Nicron H25 Headlamp Review

Nicron H25 Headlamp Review

I reached out to Nicron recently and they sent over a few lights – first this Nicron H25 headlamp!  This is a dual emitter headlamp – read on!

Official Specs and Features

Here’s a link to the Nicron H25 Headlamp Headlamp product page.


There is only one version.


The Nicron H25 Headlamp sells for a reasonable price of $40 on amazon.  That includes a single 18650.

Short Review

You had to see that orange and know right away that I’d be a fan!  I am a fan.  The dual switch, dual emitter interface is fine* (read on), and a secondary color (red) emitter is a great addition.  At $40, this seems like a solid value.

Long Review

The Big Table

Nicron H25 Headlamp
Emitter: Samsung (LH351d, probably) (Both)
Price in USD at publication time: $39.99
Cell: 1×18650
Super Bright Runtime Graph
LVP? Yes, with warning
Switch Type: E-Switch
Quiescent Current (mA): 1μA
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port with cell: no modes
without cell: no modes
Claimed Lumens (lm) 1500
Measured Lumens (at 30s) 1434 (95.6% of claim)^
Candela per Lumen 2.6
Claimed Throw (m) 120
Candela (Calculated) in cd (at 30s) 298lux @ 3.669m = 4012cd
Throw (Calculated) (m) 126.7 (105.6% of claim)^
All my Nicron reviews!


Nicron H25 Headlamp
Emitter: Samsung (LH351d, probably) (Spot)
Price in USD at publication time: $39.99
Cell: 1×18650
Super bright Runtime Graph High Runtime Graph
LVP? Yes, with warning
Switch Type: E-Switch
Quiescent Current (mA): 1μA
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port with cell: no modes
without cell: no modes
Claimed Lumens (lm) 1000
Measured Lumens (at 30s) 938 (93.8% of claim)^
Candela per Lumen 3.7
Claimed Throw (m) 120
Candela (Calculated) in cd (at 30s) 234lux @ 3.957m = 3664cd
Throw (Calculated) (m) 121.1 (100.9% of claim)^
All my Nicron reviews!


Nicron H25 Headlamp
Emitter: Samsung (LH351d, probably) (Flood)
Price in USD at publication time: $39.99
Cell: 1×18650
Super Bright Runtime Graph High Runtime Graph
LVP? Yes, with warning
Switch Type: E-Switch
Quiescent Current (mA): 1μA
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port with cell: no modes
without cell: no modes
Claimed Lumens (lm) 800
Measured Lumens (at 30s)
Candela per Lumen 0.7
Claimed Throw (m)
Candela (Calculated) in cd (at 30s) 87lux @ 3.054m = 811cd
Throw (Calculated) (m) 57.0
All my Nicron reviews!

^ Measurement disclaimer:  I am an amateur flashlight reviewer.  I don’t have $10,000 or even $1,000 worth of testing equipment.  I test output and such in PVC tubes!!  Please consider claims within 10% of what I measure to be perfectly reasonable (accurate, even).

What’s Included

Nicron H25 Headlamp what's included

  • Nicron H25 Headlamp
  • Nicron 2600mAh 18650
  • Charge cable (USB to USB-C)
  • Spare o-ring
  • Manual

Package and Manual

Nicron H25 Headlamp manual

Nicron H25 Headlamp manual

Nicron H25 Headlamp manual


Build Quality and Disassembly

Nicron H25 Headlamp feature photo

The Nicron H25 Headlamp has a nice build quality, probably packing more value than the $40 price suggests.

It’s a designated headlamp though, so there’s no real pocket-carry opportunity.  Not a huge deal.

Only one cap is removable, and the threads on this end are short.  They’re also anodized and minimally-to-appropriately lubed.

tailcap off

Only one end has a spring – the removable end.  On the other is a button.  This is probably “good” because it should serve as a notifier on which way to input the cell (if you’re used to this standard).

inside cell tube

I wanted to see if this light had the potential for emitter swaps, so I took off the front bezel.  Unfortunately, the mcpcbs with emitters are behind the electronics board.  So it’s possible, but you’ll have to remove everything to do so.

Size and Comps

Officially 2.95×1.6×1.7 inch and 4.4oz with Battery.

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

in hand

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.

beside torchlab boss 35

I said Nicron sent a few lights.  They sent this H25, but they also sent an H15!  I’m still working on this guy.

Retention and Carry

As I said, this is only a headlamp.  As such, the light comes attached to a headband.


The band itself is easily removable – you can see the gaps in the plastic piece above.  The band also has two silicone grippers and is overall very nice.  The plastic piece seems to indicate there would be a top band on this headlamp, but there is not.  I wouldn’t say it needs one unless you’re doing some high-intensity activity (and then maybe still not.)

Power and Runtime

Nicron provides the appropriate cell with the H25.  It’s a lithium-ion cell, and the H25 fits a single one only – an 18650.

included 18650

The cell is a standard button top.

included 18650

Above I mentioned the convention seen inside the H25.  Typically the negative terminal will get a spring, and the positive terminal will get either a button or a spring.  In this case, the cell goes into the light in “the usual” way – positive end goes in first.  But I can’t say “toward the head” because the “head” is really on the side.  I’ve probably confused things.  The cell goes in as seen below.  😀

included 18650 installed

With two emitters you’d probably expect a bunch of runtimes.  And I do have a few for you.  The two switches and two emitters can be seen as two independent lights.  Both can be on any level at any time without respect to what the other is doing.  So that leaves many possibilities of runtimes.  However Nicron makes the highest output claim based on both emitters being on their highest modes, so of course, I’ll test that.  Then two tests of the spotlight.

runtime graph

According to the manual, and all three of these graphs, the main (or operating) emitter will blink at low voltage as a warning.  The charts display that.

runtime graph runtime graph

This is where I ran into a mess on my H25.  I could not make the floodlight stay on for longer than exactly one minute on either of the highest two modes.  That obviously complicates runtimes… I spoke with Nicron about this and they’re still looking into a solution.  This feature (which is very clearly programming, and not a light fault) does not seem to be documented in the manual (which is provided above).  The cell was fully charged, and despite the user interface being a little unusual, I was able to use it successfully (as evidenced by successful use with the spot beam, which worked fine.)  I will certainly keep you updated.

Nicron was kind enough to send out a fresh H25 for testing specifically the Flood light. I think this is indicative of the service you’d receive if you received a light that has some unexpected behavior.  So this is actually a good bit of information about Nicron.  Good customer service!  It didn’t seem that I received this light just because I’m a flashlight tester; I expect you’d get the same service.

So here are a couple of runtime graphs on the Flood light of the H25.  It’s quite bright!


USB-C is the way of charging on this Nicron H25 Headlamp.  The USB-C port is protected by a press-in rubber cover.  It’s not the best cover I’ve seen; a little flimsy and by default “more out than in.”  Beside the charge port is a charge indicator.

An appropriate cable is included – USB to USB-C.

As I’ve been trying to do lately, I tested charging both ways – from a USB source, and from a USB-C source.  Both work fine.  Charging actually looks great, at around 1.2A (nearly 0.5C, so “ideal”) and the CC phase is very consistent.  Termination voltage is “a little low” but not really – as you can see the added mAh to “full” is minimal (read: negligible).

charge graph

Modes and Currents

Emitter Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
Both Turbo (High of both emitters) 1500 1434 6.56
Spotlight “Super Bright” 1000 2h 983 3.10
Spotlight High 500 3h 612 1.73
Spotlight Middle 250 6h 317 0.68
Spotlight Low 50 30h 62 0.18
Floodlight “Super Bright” 800 2h 834 2.95
Floodlight High 400 3h 466 1.66
Floodlight Middle 200 6h 234 0.58
Floodlight Low 50 30h 47 0.17
Red On 0.05

Pulse Width Modulation

Aside from the user interface issue, my biggest gripe with the h25 is the PWM.  The default mode order is Highest to lowest, which is how the graphs below are presented.  Every mode has PWM, and on the lower modes, it is absolutely visible.



Both (High):

pwm graph


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, with is 50 microseconds (50us).  10ms5ms2ms1ms0.5ms0.2ms.  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

Two switches are used for the operation of the Nicron H25 Headlamp.  One’s a power switch (and has a power symbol, and Nicron calls this one “Switch A”) and the other one controls the floodlight and is called “Switch B.”)

dual e-switches

These are very low action, low profile e-switches.  I like them quite a bit.  They’re big enough to get on easily, but they’re sleek enough that you’re very unlikely to click them accidentally.

Here’s a UI table!  Remember that the switches each completely control their respective emitters.  Almost everything that goes for one emitter goes for both (with two exceptions.)  I’m also describing the default user interface, which can be reversed.

State Action Result
Off Hold Switch A (1.2s) Spot High
Spot On Click Switch A Mode advance (High to Low direction)
Spot On Hold Switch A Spot Off
Off Click Switch A Battery indicatorª
Off Hold Both (1.2s)^ Turbo (both emitters on)
Off Hold Switch B (1.2s) Flood High
Flood On Click Switch B Mode advance (High to Low direction)
Flood On Hold Switch B Flood Off
Off Click Switch B Red (steady)
Red Click Switch B Red advance (Blink, off)
Off Hold either for 10s Reverse mode order (for both emitters)

^ Technically the manual graphic indicates “holding both” would go to Turbo (both emitters on highest), but in reality I found it to require separate actions – click one emitter to the highest output, then click the other to the highest output (per the required steps in the table above.)  Holding both to get to turbo would be the ideal option, though.  This brings up the point that the graphic in the manual isn’t completely clear.

ª Battery indication displays as follows:

Four blinks (of spot emitter): >90% capacity
Three blinks (of spot emitter): 70-90% capacity
Two blinks (of spot emitter): 30-70% capacity
One blink (of spot emitter): <30% capacity

It is possible to have not only both white emitters on at one time but also Spot and Red on at the same time.  (The limitation of “Spot” and red (and no Flood) is probably because the flood switch controls red too – can’t control both at once with the same switch.

Aside from the bug in my user interface that caused the floodlight to go off on its own after exactly 1 minute (which if written as a feature might not be the worst feature ever!), there was also quite a few instances where clicking (not holding) Switch B didn’t go to red, but to the flood modes.  I can’t explain it, and I’m eagerly awaiting Nicron to explain it, too.  I’m interested to see if the H15 has this as well (and will know soon enough.)

LED and Beam

Nicron utilizes two of what I take to be the same emitters in the H25.  These are Samsung emitters, but Nicron doesn’t state which ones specifically.  They’re almost certainly LH351d (awesome!) but also almost certainly on the cooler side.


That’s not necessarily bad – in my beamshots below, you can see this as a more “stark white” than really cool white.  And I don’t see any green!


The emitters may be exactly the same, but the reflectors are not – one (the spot) has a smooth reflector, and the other (the flood) has a wavy reflector.

emitter on

The red emitter sits deep-ish into the body, which results in a pleasantly tight beam.

red emitter on

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



Both (High):

beamshots ceiling


beamshots ceiling

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

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



Both (High):

beamshots door compared to nichia 219b


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


What I like

  • Remarkably low quiescent current
  • Very good USB-C charge profile
  • C to C charging works
  • Dual emitters fit their job well (flood is floody, spot it spotty)
  • Good user interface
  • It’s orange!
  • Hits output claims
  • Hits throw claims

What I don’t like

  • PWM on all modes
  • My flood … didn’t work right.
  • Cool white emitters (Flood as warm would have been great!)
  • Modding is not really a good possibility


  • This light was provided by Nicron for review. I was not paid to write this review.
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