Sofirn SC13 Flashlight Review

Sofirn SC13 Flashlight Review

The Sofirn SC13 flashlight is the newest 18350 Luminus SST-40 offering, with USB-C charging and an indicating switch. The tail has a magnet, too. Read on!

Official Specs and Features

Here’s a link to the Sofirn SC13 flashlight product page.


There’s just one version of the Sofirn SC13 flashlight but it’s available with or without the 18350 cell.


With the cell (which is what you should buy), the Sofirn SC13 flashlight is only $32.99!

What’s Included

Sofirn SC13 flashlight what's included

  • Sofirn SC13 flashlight
  • Sofirn 1100mAh 18350
  • Pocket clip
  • Lanyard
  • Charging cable
  • Spare o-rings (2)
  • Manual

Package and Manual

Sofirn SC13 flashlight box

Sofirn SC13 flashlight manual

Build Quality and Disassembly

Sofirn SC13 flashlight

The build quality is fine. There’s nothing bad to say here.

The tailcap therads are well-lubed and long. The head does not come off – the body is one part.

Sofirn SC13 flashlight tailcap off showing threads

Below you can see the positive terminal – just a button. A nicer build quality would probably include a spring, but this button does work just fine in a non-tactical light like this one.

Sofirn SC13 flashlight showing button in body

Size and Comps

28.5mm x 64.6mm and 40g without the 18350.

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

Sofirn SC13 flashlight in hand

Here’s the test light with the venerable Convoy S2+. The version you see below is a custom Convoy S2+ host that’s been laser engraved by I did a full post on an engraved orange host right here! Or just go straight to to buy your Convoy S2+ now!

Also above is the light beside a TorchLAB BOSS 35, an 18350 light. I reviewed the aluminum version of that light in both 35 and 70 formats. I also reviewed that specific edition, the “Oveready BOSS FT Collector Vintage Brass” 35. I love it!

Retention and Carry

Sofirn includes a friction-fit pocket clip with the SC13 flashlight.

Sofirn SC13 flashlight pocket clip

This clip attaches only on the very front-most part of the SC13. The clip can’t go anywhere else, and I’d say also that the light looks weird without the clip, too.

Sofirn SC13 flashlight pocket clip

A lanyard is included, and it attaches through this loop in the tailcap. You could also use the pocket clip hole, too.

Sofirn SC13 flashlight lanyard hole

Sofirn SC13 flashlight lanyard

And finally, there’s the magnet in the tailcap. This magnet is perfectly sufficient for attaching the SC13 to things!

Sofirn SC13 flashlight tailcap magnet in use

Power and Runtime

The package price (which adds just $2 to the base price of the SC13) includes an 1100mAh 18350 cell. It’s a button top cell.

Sofirn SC13 flashlight with included cell

The cell goes with the button toward the head.

Sofirn SC13 flashlight with included cell in place

If you forget that orientation, you can observe the battery orientation indicator on the tailcap.

Sofirn SC13 flashlight battery direction indicator

Below are a few runtime tests. The light does not seem to hit the claimed 1300 lumens. It does have high output though, for a minute or so – around 1000 lumens. That’s quite impressive, even if it’s not the claimed 1300 lumens. The stepdowns after a minute are dramatic, to around 300 lumens.

Sofirn SC13 flashlight runtime graph

Sofirn SC13 flashlight runtime graph

Sofirn SC13 flashlight runtime graph

Sofirn SC13 flashlight runtime graph

Low voltage protection was observed in every test and the switch will also indicate the power level (as follows):

Green: 70-100% power
Red: 30-70% power
Red flashing: 0-30% power


Charging is built in. There’s a USB-C port in the head. This port has a press-in cover.

A USB to USB-C charging cable is included, too.

Sofirn SC13 flashlight charging cable

Below you can see a C to C and A to C charging test. They’re both very good – steady charging at around 1C, with completion at around 1.5 hours.

Sofirn SC13 flashlight

Sofirn SC13 flashlight
While charging, the switch is red. When charging is complete, the switch turns green.

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
Turbo 1300-500 2m+1h20m 1060 (0s)
1002 (30s)
High 500 1h30m 411 1.06
Medium 150 3h30m 139 0.38
Low 10 17h36m 8.3 0.03
Moonlight 1 100h 0.9 [low]

Pulse Width Modulation

Only the lowest mode doesn’t use PWM. The other modes use fairly fast PWM, though.

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 Sofirn SC13 flashlight is controlled by a single indicating e-switch.

Sofirn SC13 flashlight indicating switch

I like this switch (so this is not a complaint): it has a good bit of travel (but it’s clean travel and not mushy). There’s also a hollow-ish sound when clicking that you’ll probably notice (but not hate).

Sofirn SC13 flashlight switch actuation

Here’s a UI table!

State Action Result
Off Click On (Memory)
On Click Off
On Hold Mode advance (LMH)
Off Hold Moonlight
Any Double click Turbo
Turbo Double click Strobe
Strobe Double click Turbo
Off Click 3x Lockout (LED flashes twice to indicate)
Locked Click 3x Unlock to on (Mode memory)
Locked Hold Momentary Moonlight
Locked Click LED flashes twice to indicate lockout

LED and Beam

Sofirn went with a Luminus SST-40 in this tiny little light. That emitter is coupled with a “ripple” TIR.

Sofirn SC13 flashlight emitter and TIR

Sofirn SC13 flashlight emitter on and TIR

Sofirn SC13 flashlight emitter on

LED Color Report (CRI and CCT)

The box of my SC13 says the output is between 6000K and 6500K. My tests indicate it at least starts a bit warmer than that (around 5300K) but then does cool off (to around 6200K) as the output gets higher. CRI is low.


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

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.

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

Summary and Conclusion

I happen to love 18350 flashlights and I’m pleased to see the SC13 offering by Sofirn. The user interface is nice and simple while offering the features I want, and overall the performance is fine. I would prefer a warmer CCT and (much) higher CRI, but this is a nice start. USB-C charging works great, too.

All this for around $30, and the Sofirn SC13 flashlight seems like a deal.

The Big Table

Sofirn SC13 Flashlight
Emitter: Luminus SST-40 (6000-6500)
Price in USD at publication time: $30.99
Cell: 1×18350
Runtime Graphs
LVP? Yes
Switch Type: E-Switch
Quiescent Current (mA): ?
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port with or without cell or tailcap: lowest three modes
Claimed Lumens (lm) 1300
Measured Lumens (at 30s) 1002 (77.1% of claim)^
Candela per Lumen 8.82
Claimed Throw (m) 217
Candela (Calculated) in cd (at 30s) 401lux @ 4.856m = 9456cd
Throw (Calculated) (m) 194.5 (89.6% of claim)^
Claimed CCT 6000-6500
Measured CCT Range (K) 5300-6200 Kelvin
Item provided for review by: Sofirn
All my Sofirn 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 I like

  • Good build quality especially for the price
  • Complete pacakge
  • Runs an 18350 cell
  • Good e-switch
  • Simple but useful user interface
  • Good tailcap magnet

What I don’t like

  • Low CRI
  • Cool white
  • If you don’t install the pocket clip the head looks sort of weird (like you forgot to add a part)
  • Does not quite hit output specification


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