[Review] Sofirn IF25A flashlight: $34 (discount code available) 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.

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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

  • 18650 with protection circuit
  • Flat top 18650 VTC5A
  • Flat top 18650 VTC5A
  • Plenty of room for spring

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

  • IF25A, SC31B, SD05
  • D4, IF25A, MS03, SC31B, SD05
  • D4, IF25A, MS03, SC31B, SD05
IF25A compared to some other single cell lights

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

  • Anduril UI

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.

  • Green for standby
  • Red when taking current
  • Orange in candlelight mode!

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.

  • Taking the optic out
  • Beam profile as a mule

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.

IF25A 6500K SST20, D4 4000K XP-L HI



  • 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.
Update: Sofirn have provided some discount codes for their Amazon UK store.
  • SP40 30% discount: G4SR6J9Y
  • C8F 30% discount: S7OXU4Q9
  • IF25A 20% discount: HBIY3QF5 [ discount price: 31.71, original price47.99 ]
They also have a 20% discount on some products, bringing the price down 40%.

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.

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

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 x 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.

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)

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

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.

Dear friends, good morning from Italy! I would like to add a mode that I don’t see written in this review. The mode is this: by making 7 clicks from off it is possible to activate or deactivate the LEDs on the power button; even with the flashlight off, therefore, there will be no LEDs on if deactivated with the 7 clicks from off. This seems convenient, if we do not want to consume that minimum current of the LEDs always on. :beer:

Normally, 7 clicks from Off configures the Aux-LED (for Anduril flashlights that have configurable aux-LED).
For some Anduril flashlights, this setting is connected to the side button switch (eg. the SP36, EC01, EC03, Q8 , SC31 Pro side button also lights up the same way).

7 clicks will cycle from Off -> Low (default) -> High -> Blinking (breathing) -> Off.
High uses a somewhat higher amount of power. Blinking uses less power, and the default Low actually uses very little power, just slightly higher than Off.

Just an FYI.
The Olight Traffic Wand/Diffuser works on the IF25A. The Olight diffuser mounts to the IF25A more securely than it does to the Seeker2/Pro and Warrior X.
Only caveat is, the light option must be selected first, since the button is not accessible once attached to the diffuser.
They can be found here, since Olight no longer sells them. Battery Junction/Seeker2/Pro Diffuser/Traffic Wand

The Olight diffuser/traffic wand is made of very hard, and strong, unbreakable plastic.

I have this light (IF25A). I brought it from the Sofirn store. I was disappointed it didn’t have the same version of Anduril as the BLF SP36 that I also brought from Sofirn at the same time. The version on the IF25A is older and didn’t have the useful feature where hold from off for moonlight delays going on until the hold is valid.

Sofirn’s other brand, Wurkkos, recently released a HD20 headlamp that can also function as usb-c battery to charge your phone. It’s odd they did that for a headlamp, but their handheld line of lights do not have the charge feature.

I’d get another IF25A if they add USB battery feature on the next edition.

could you elaborate on ‘until the hold is valid’? i love being able to hold on the LT1 to get the lowest setting from off.

my guess for the the USB power bank thing is that they have older stock of the earlier firmware/hardware resistors etc.
my LT1 has newer firmware with SOS, but i think it lacks the resistors for power bank.

i’m tempted to get this light, but if a version with newer firmware that includes SOS is going to be available i just may wait.

[edit] thanks for the review dave1010. :+1:

Sorry, what I said was kinda vague and the feature change in Anduril itself is very nuanced. The current IF25A’s firmware has the older Anduril where you get shortcut to moonlight if you hold from off, but the moment you click, the light comes on in moonlight, and when you release after the required delay, it stays in moonlight. If you release too soon (so that the IF25A doesn’t see it as a hold), it goes to the last used setting even if you intended it to be hold. There’s a very slight feedback by blinking the LED to tell you that you’ve held it long enough. If you overhold, the light start ramping up.

Contrast that to the latest Anduril (like the on BLF SP36). You hold from off to get to moonlight, just like the previous version. But the moment you click down, the light stays off until the hold time is met. That means you get a slight delay after clicking down when you start the hold, but the light turning on in moonlight is your cue that you’ve held down long enough and you should let go before you overhold and the light starts ramping.

It’s such a minor change, but the delay really helps you avoid holding too long (and start ramping up) or holding too short (ending in previous brightness mode). ToyKeeper does a great job making these effective UI features.

thanks for the detailed explanation river345. :+1:
i can see how that would be annoying. especially if memory was the ceiling. :weary:

agreed, ToyKeeper does amazing work. wish manufacturers would make flashing easier.

Oh that’s another strike against the IF25A. It’s difficult to flash.

does anyone make it easier? if not, can we even count that as a strike? :stuck_out_tongue:

thanks for the info flashburn. (fitting name heh)

How does the If25A beam profile compare to the SP 33V3. The 33 has a sustainable 500 lumens. Any idea what the 25A has?

Thanks for the review!
I recently got mine and can’t unscrew the front bezel to gain access to the TIR optics. It feels like it’s glued, I put so much effort but didn’t achieve a thing.

Hmm, it might be snug but I didn’t find my IF25 to have a glued bezel.
Are you using just your hands? Have you tried something like one of those rubber jar openers, or a strap wrench maybe?

My hands mainly. I then used some rubber gripping material but still no luck. Maybe I’m just weak :stuck_out_tongue: