[Review] Sofirn IF25A flashlight: $34 with 21700 cell, 3800lm, USB-C, Anduril [pic heavy]

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dave1010's picture
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Location: Dorset, United Kingdom
[Review] Sofirn IF25A flashlight: $34 with 21700 cell, 3800lm, USB-C, Anduril [pic heavy]

Another light from Sofirn I’m reviewing is the IF25A. This is a pocketable flashlight with 4 LEDs.

[Right click / long press and open images in a new tab to see full size]


About the light

The IF25A is small but powerful budget light. It takes a 21700 cell and has 4 SST20 LEDs, pumping out up to 3800 lumens. It has an E-switch and uses the Anduril flashlight user interface. It also has USB-C charging built into the light.


The light is available on Amazon UK now with a cell included and will probably be on Amazon US soon. You can also buy the IF25A from Sofirn’s official store. Different places seem to include either a 4800mAh cell or 4000mAh one.


The IF25A is an updated version of the Sofirn IF25. The updated version sacrifices the tint ramping for more lumens. The tint ramping in the original IF25 allowed you to fade between cool white and warm white.

Flashlight LEDs
IF25 2 x 95CRI 2700K SST20 and 2 x 70CRI 6500K SST20
IF25A 6500K cool white 4 x 70CRI 6500K SST20
IF25A 4000K warm white 4 x 95CRI 4000K SST20
Sofirn IF25 / IF25A versions

I’m reviewing the cool white IF25A, which has more lumens than the warm white one.

Sofirn IF25A specs

Lumens 3800lm
LED 70CRI 6500K SST20
Cell 21700. Mine came with a 4000mAh cell and also a sleeve to fit some 18650 cells
Optic TIR lens (instead of a reflector)
Voltage 3.0V – 4.2V
Size 106.4mm length × 35mm head diameter. I measured the body between and 25.4mm and 31.0mm
Weight 99g without battery. I measured 165g with the 21700
Material 6061 aluminum alloy, hard-anodized with anti-abrasive finish. Toughened mineral glass lens
Switch Side e-switch
Waterproof / Ingress protection Unknown
Official specs

The physical light

What’s in the box

The IF25A comes in a printed cardboard box. I received the “kit” version, which includes the cell and a few extras:

  • Sofirn IF25A flashlight
  • 4000mAh cell (some shop listings show a 4800mAh cell)
  • a 65mm long 18650 to 21700 sleeve
  • Manual
  • USB-A to USB-C cable
  • Lanyard
  • Spare O-rings

Appearance and quality

The IF25A is well machined but it has sharp corners on the fins and lanyard hole. This hasn’t caused any issues with daily use but doesn’t feel as high quality as other lights, including some of Sofirn’s. The rest of the body is chamfered nicely.

Anodising and threads seem good, just like Sofirn’s other lights.

Cell compatibility

The IF25A has a medium-thick spring on the tail end and a flat connection on the head end. 21700 cells fit in well and don’t loose connection when the light is knocked. Longer 18650 cells (button top or ones with protection or circuit) are fine too but I found a flat top 18650 (VTC5A) would loose connection when the IF25A was shaken. I’d recommend button top 18650 cells or any 21700 cell for this.

The white sleeve is also a bit loose in the IF25A and you can hear it move around a bit when shaken or tilted. A bit of paper between the sleeve and light fixes this.

Physical comparison

The IF25A is pretty small for a 21700 light and is the shortest one I’ve seen. It’s shorter than Sofirn’s SC31B and SP40, both of which are 18650 lights. Parametrek lists the Lumintop FW21, FW21 Pro, Zebralight SC700d and SC700Fd as a few mm shorter but taking 21700 cells.


Carrying and everyday use

There’s no pocket clip with the IF25A but it comes with a (sharp!) lanyard hole. The lanyard hole is on one edge and still allows tail standing.

Without a clip though, it either needs to be loose in a pocket or in a pouch with a belt clip. That makes it not quite as good for EDC. There’s a couple of places on the body that a clip could go but you’d need one that stretched to 25.4mm. The IF25A would fit in a pocket if you’re used to carrying large 18650-sized lights.

Without a clip and with a fairly round smooth body the IF25A rolls quite a bit when on a table. This made photos awkward and I dropped it a couple of times.

Interface and switch

The IF25A has a lighted E-switch and uses the Anduril UI. I’ve written about flashlight UIs and Anduril before, so won’t repeat that here. The basics is:

  • Click on
  • Click off
  • Hold to change brightness

Sofirn have used a slightly older version of Anduril, so doesn’t have a few of the newer features like showing the build version. There doesn’t seem to be easy access to the driver (at least with my skill level) if you wanted to update it.

As with most Anduril lights, there’s thermal throttling that might need configuring with a special series of clicks. Otherwise it may step down from turbo too quickly or too slowly. Mine said it room temperature was 26°C when it was actually 21°C. You can read my quick guide on the Anduril thermal config here.

The switch itself has 2 green indicating LEDs on it and seems to click well.

Cell and USB-C charging

Sofirn IF25A comes with built in USB-C charging under a rubber cover. The cover seems fairly good but as with nearly all built in charging, it’ll make the light less waterproof.

The IF25A does lacks the circuitry to support the use of a C-to-C charging cable, so needs an A-to-C one. I saw the IF25A charge at up to 1.3A. The e-switch lights up red when charging and green when done.

You can also power the light via USB, though not to maximum brightness. The red indicating light comes on when you do this, to show it’s taking current from the charger. I noticed that Anduril’s candlelight mode flickered the green and red indicating light when USB powered, to make a nice orange colour. This might be a bug that turned into a feature.


Light output


As with other Anduril lights, the IF25A has smooth brightness ramping, so you can pick any brightness from around 1 lumen up to the maximum of 3800 lumens. You can also change it to stepped ramping and specify your own min, max and number of steps.

LED and beam, PWM

The IF25A uses 4 TIR optics instead of 4 reflectors. This means the light can be shorter and seems to help make a smoother graduation between hotspot and spill. The PWM isn’t noticeable to my eyes on the IF25A.

You can also take the optic out, and put the bezel back on, which changes the light into an almost 180° wide angle mule. This is great for indoor use.

With the optics back in, the light is fairly throwy for a small multi emitter light. Here’s the beam compared to my D4 4000K XP-L HI. The 6500K version is very cool for my liking, so I’d have picked the 4000K version if it was on Amazon.




  • Bright at 3800lm with a good beam profile
  • Built in USB-C charging
  • Compact size
  • 4000K tint option available


  • Some sharp edges
  • No pocket clip
  • Anduril version is fairly old

Potential changes and improvements

If Sofirn make an upgraded version of the IF25A, I’d like to see:

  • C-to-C charging (and power bank functionality if possible)
  • Flashing pads on the driver, so Anduril can be updated and tweaked easily


The Sofirn IF25A has a few minor issues but they’re balanced out by the power, capabilities and features of the light. The built in charging is great but it won’t replace my D4 as my EDC due to lack of a good clip.


 Thanks to Sofirn for providing the light for review.

https://davestechreviews.wordpress.com/ / Email: <my BLF username>@gmail.com

Last seen: 1 week 2 days ago
Joined: 12/29/2019 - 03:38
Posts: 215
Location: WA

Thanks for the review. Looks to be a good holiday gift. USB charging definitely good for those without chargers (most non-flashlight folk I know). Price in line with others at this size/brightness. Some OK tint options but only SST20. I think this is another great light from Sofirn.

dave1010's picture
Last seen: 10 hours 15 min ago
Joined: 07/04/2017 - 02:38
Posts: 90
Location: Dorset, United Kingdom
YogibearAl wrote:
Looks to be a good holiday gift.

Yeah, USB-C chargiy makes it a great gift. Also:

  • Great UI – easy to pick up but there’s lots of advanced modes to get people doing their own research
  • Fairly cheap
  • Fairly small but enough mass and lower output for it to be safer than an Emisar D4
  • Good balance of flood and throw

https://davestechreviews.wordpress.com/ / Email: <my BLF username>@gmail.com

Last seen: 2 days 22 hours ago
Joined: 03/11/2020 - 20:25
Posts: 109
Location: Sydney, Australia

I received mine a few weeks ago.
I noted that it still had the two separate positive wires from the driver like the tint mixing version.
I had been thinking about doing a static mix of shaved SST-20 emitters and thought this might actually deal with the different forward voltage better than most because of it.
Anyway, i shaved 2 × 4000k stock SST20 (Sofirn have some of the better bins of the 4000k), then added two shaved 2700k JA3 emitters.
The mix is very nice. the JA3 are very rosy already, plus the mix went well and brought the BBL waaaaay below.
I forgot my spectrometer results, i think it was something like 3000k, -0.0060 @ RA98 on turbo. Very beautiful to my eyes indoors, possibly too rosy for some though. Down low is quite a bit higher.
The interface is obviously great, the optics have some really good throw to them (Even in the original), there is a lot of mass for dealing with heat.
Only thing i would change is the driver i suspect is a simply PWM FET design, not very efficient. Not the end of the world with a 21700 cell and some mass to the light, but it kind of takes away some of the advantages.
If they ended up building a nice boost driver or something for it, it would be the perfect mid-sized pocket rocket.

A great allround multi-emitter light to talk walking or away for the weekend for use in doors thanks to the USB-C, 21700 cell and decent throw.

Last seen: 2 hours 59 min ago
Joined: 08/04/2017 - 23:58
Posts: 1999
Location: Manila, Philippines

I’d like to ask (I notice that Sofirn has been updating the firmware of their Anduril flashlights).

For those who just received the IF25A fairly recently (say within the last month or 2), can you do Anduril version check (15 clicks from Off) to check if it’s a newer version of Anduril? (older IF25A does not have version check, and used a fairly old Anduril version that doesn’t have the 2-level lockout or momentary strobe mode)

dave1010's picture
Last seen: 10 hours 15 min ago
Joined: 07/04/2017 - 02:38
Posts: 90
Location: Dorset, United Kingdom

Mine came from Amazon UK a few weeks ago and doesn’t have version check or dual moon modes

https://davestechreviews.wordpress.com/ / Email: <my BLF username>@gmail.com

Lightbringer's picture
Last seen: 1 hour 22 min ago
Joined: 08/30/2016 - 14:12
Posts: 12246
Location: nyc

Huh… interesting.

I wasn’t interested in the original with the tint-ramping, but the ‘A version looks pretty useful.

I’d definitely go only for the 4000K version, though. 6500K is killing me.

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