REVIEW: Sofirn SP31 V2.0 [18650, XPL HI, dual switch]

This is my review of the Sofirn SP31 V2.0. The flashlight has been supplied by Sofirn for review. Thank you very much, Sofirn!


The Sofirn SP31 is a 18650 flashlight with dual switch. The side switch is easier to reach and press than the tailswitch and gives the flashlight a better handling. This flashlight has some nice high-end features that are found only on flashlights developed with attention to details, for example an AR coated glass lens, square cut, anodized threads and four modes with hidden strobe and SOS. The Sofirn SP31 V2.0 is apparently the successor of the SP31 that had a XPL2 V6 but less rated lumens.

Purchase links (non affiliate)
Amazon IT: with battery:

without battery:

Amazon DE:

Amazon US:


First impressions

I have a few Sofirn flashlights and know from my experience and from BLF that their quality is high with nice features for flashlight experts. I can confirm that this applies also to the SP31 V2.0. The anodising is matte black, the threads are square cut and there are more than the usual three modes. What I also like is the dual switch design. You can switch the flashlight off with a tail switch and change modes with the side switch.

This is the Sofirn cardbox and what is inside

What is included

- Sofirn SP31 V2.0

- lanyard

- two spare o-rings

- 18650 Sofirn battery 3000mAh

- single slot battery charger

- Micro USB cable

- manual

  • card with contact address


These are mostly the specifications claimed by Sofirn. I did not test the lumen, throw or waterproofness but they seem to be reasonable.


- AR coated glass lens

- Smooth reflector

- Battery: 18650 or 2x CR123A

- Voltage: 2.8-6.6V

- Dimensions: 23.4mm(body diameter)*133.5mm(length)

- Weight: 72g

- Weight with battery: 119 g

- IPX8 Water resistant, underwater 2 meters for 30 minutes

- Low Voltage Protection

- Reverse polarity protection

  • Advanced temperature regulation (ATR 60°C)

Modes and runtime

- 5 modes: Eco; Low; Med; High; Turbo; with mode memory; hidden strobe and SOS

- Eco: 5Lumens (291 hr.)

- Low: 50Lumens (26 h 49 min.)

- Mid: 160Lumens (9 hr 45 min.)

- High: 500Lumens (3 hr 41 min.)

  • Turbo: 1200Lumens (2 hr 37 min.)

Runtime table in the manual:


Flashlight length: 133,6 mm
Head length: 53,5 mm
Head diameter: 26,0 mm
Reflector ID: 17,7 mm
Battery tube length: 71,7 mm
Battery tube OD: 23,6 mm
Diameter at threads (both ends): 22,2 mm
Battery tube ID: 18,9 mm
Tailcap length: 30,6 mm
Tailcap diameter: 23,9 mm
Battery length: 66,9 mm
Battery diameter: 18,5 mm
Spring wire diameter (both ends): 0,7mm
Driver diameter: 20,0 mm

Note: The head of the flashlight is impossible to open with bare hands and therefore other dimensions of the reflector or PCB are unknown. The driver is glued inside as well.

User interface

The flashlight is turned on with the forward clicky tailcap switch. Because the threads are anodized you can turn off or lock out the light also by slightly unscrewing the tailcap or head. As the switch is forward clicky it can be pressed only halfway for momentary lighting. You can change modes with the momentary side switch. There are five modes and hidden strobe and SOS mode. With a short press you cycle through the modes, with a long press you can access strobe and SOS. A short press goes from strobe to SOS (loop) and another long press exits the hidden modes.
The user interface is simple and easy to learn and operate. However, I miss a few more sophisticated functions here. I would add a direct access to turbo with double click and a possibility to return to the previous, dimmer mode. Also I would like to turn the flashlight off with the side switch as it is easier to reach than the tailswitch. The five modes are well spaced and useful but the lowest mode could be lower to be a proper moonlight mode.

The Sofirn SP31 V2.0 in use


Front view

Rear view (14 mm button)

Four different side perspectives

The three parts of the flashlight: head, battery tube and tailcap

The XPL HI in a smooth reflector is good for throw. It is not perfectly centered but in a small reflector this shouldn’t matter.

The threads are nicely square cut but apparently not lubed. They are anodized to allow physical lockout. The tailcap and the head screw on and off very smoothly.

The glass lens is AR coated, just look at the purple reflection on the glass.

The battery indicator light in the side switch lights green a few seconds when the flashlight is turned on and the battery voltage is high enough.

The battery indicator is steady red if the battery is below a certain voltage and flashes when the battery needs to be changed while the light steps down.

Remember to remove this battery cover before turning on the flashlight for the first time. It falls out anyway when you unscrew the tailcap and prevents the flashlight from short circuit or accidental turn on during shipping.

The head with the hot symbol (don’t touch it after one or two minutes runtime on turbo!)

Driver close-up (mind the glue around the retaining ring)

The threads are the same on both ends so the battery tube can be reversed. This way, you can change the position of the clip and clip it inside your pocket or on a hat.

Battery and charger

The battery is button top and a rewrapped quality cell with Sofirn branding. Judging from weight and charging time I would say that the 3000mAh of the battery are an accurate value. It delivers enough amperes to make the SP31 run hot on turbo.

The charger is a simple single slot charger that charges with 4.2V and 0.75A. It has a slider so that different lengths of batteries will fit. It can recharge all sizes from 16340 to 26650. The charging current is appropriate for 18650 or 26650 batteries as it is 0.2 to 0.3C. With the supplied USB cable it can be connected to any 5V power supply with USB output. I really prefer an external charger over an integrated USB charging in the flashlight.

Comparison pictures

Big Sofirn lights (from left to right): 18650 Sofirn battery, Sofirn SP31 V2.0, Sofirn C8F, BLF Q8

Small Sofirn lights (from left to right): Sofirn SP31 V2.0, Sofirn SF10, Sofirn SP10S, Sofirn C01S

Some well known flashlights (from left to right): 18650 Sofirn battery, Sofirn SP31 V2.0, Convoy S2, CPF Italia Cometa (Jaxman Z1 clone), Convoy C8


The beam has a wide spill with a tight hotspot, as can be seen here in a white wall beamshot.

This is a comparison shot with the Emisar D4S 219C at highest regulated mode (approximately 400 lumens). You see that the SP31 V2.0 is a bit colder and obviously not 90 CRI like the Nichia 219C. At 1200 lumen the SP31 has more candela per lumen, meaning that it reaches further / is throwier than the D4S at the same brightness level.

Outdoor beamshot on turbo, the trees are about 100 meters away. (2s, F7.1, ISO 500)

Control shot without flashlight (same settings)


My overall impression of the Sofirn SP31 V2.0 is very good. It offers everything a flashlight needs to have and the handling is very nice. It can be used by occasional flashlight users as well as experts. There are a few tweaks that could be made but on overall it is a well-made flashlight.

What I like

- good quality black anodising

- square cut threads for smooth threading, anodized for lockout

- double switch design

- AR coated glass lens

- four even spaced modes

- hidden strobe and SOS mode

- almost neutral white led

  • nice battery and charger

What could be improved

- more sophisticated UI with direct access to turbo and an option to go back through the modes

- maybe lower moonlight mode

  • second tint choice with 4000K

Many thanks to everyone for reading! If you have any questions or want more information feel free to comment below.


Do you know if the memory works for strobe? Or does it change back to the normal modes once it’s powered on again? Also thanks for the great review. It’s weird how no has anything to say sometimes. I’m sure quite a few people found your information useful.

SP31v2.0’s strobe mode is not memorized, changes back to normal mode when it’s powered on again.

That’s unfortunate for my use. But probably for the best experience. Thanks.

Sofirn once wanted my opinion about this light. I told them strobe needs to have memory and the preflash must go.

They all never listen. But iirc, there’s a new model that can do it. Can’t remember which one it was.

Agree, if strobe was memorized (as it was in the TK15S/SP31v1) and also constant frequency, they would have had massive sales to light painting photographers. But they didn’t.

Just verified that the strobe is indeed not memorized. The SP31 V2.0 always goes back to the last used mode after you turned it off and on again.

While having the strobe running I also noticed that the strobe changes frequency every few seconds. It goes fast and then it goes twice as fast, slower again and so on. I don’t know if this is a known fact but I didn’t notice it until now. It seems to be a ‘tactical’ strobe for disorientation.

Not sure if a frequency changing strobe is useful for light painting…

WastedNihilist, thank you for your nice comment that brought my old and empty review thread back to live. :sunglasses:

Light painters generally hate alternating frequency strobes. We much prefer constant frequency, or even better constant frequency with the ability to adjust the frequency (as per Anduril and LightPainter - Ryu’s Lightworks firmware). Sadly alternating frequency strobes seem to be an increasing trend.

Hmm, I saw the SP31v2 and thought “Hmm, that’s an oldie, no?”. :laughing:

I got one of the originals. This looks like a pretty good thrower.

Just ordered a second one from Sofirn’s website. Now they offer it with LH351D 4000K so I couldn’t resist.

SP31v2.0 is still the flashlight I suggest in our local flashlight community when someone asks me for a more-or-less cylindrical-shape EDC size flashlight that throws fairly well (compared to similar-head-size EDC flashlights). The alternative would be the Convoy S2+ (or Convoy S2) with XPL-Hi or SST20. But the momentary tail-switch function of the SP31v2.0 seems to be a bit less common for EDC flashlights in this budget level.

My other suggestion for a throwy pocketable light (aside from the bigger head GT Micro / BLF X5 / Emisar D1) could be the Amutorch Yootoo SD2 (SST20, 21700 battery) which is also quite throwy, but the build quality seems to be a bit less than Sofirn/Convoy. The Manta Ray S21 with Osram NM1 (21700), is also quite throwy for EDC-size flashlights, since it uses the Osram NM1 (W1) LED…