**REVIEW** Sofirn SC31 USB Rechargeable

I don't get many private messages but I had a pleasant surprise this past week when I received a request from Sofirn to review the SC31. Apparently, a few other BLFers received requests too so I'm a little late in getting mine out. There's nothing like putting a product in the hands of a user to see what happens so here are my observations.

The light is offered as a kit including the light, battery and micro USB cable.

So, looking at the kit components:

The lights' emitter is a Cree XP-G3 and coupled to the orange peel reflector, it produces an almost cold white hot spot with a warmer spill. The boundary between spill and spot is not hard but it has a quick transition.

The three modes are well separated and either pressing the switch for more than a second or constantly holding it will change to the next mode. A double-click with the light off as well as with it on will activate a dual frequency strobe. A single click in any mode will simply turn off the light. And when you single-click the light again, it will turn on in the last used of the three regular modes. A special feature of the this light is the blue-lit switch that acts as a charging indicator, state of charge indicator and when you long-press it while off, a slowly pulsing pattern emanates from the switch.

Physically, the light has a comfortable feel. The switch boot is larger than other Sofirn lights and is easily located by feel. The switch allows you to activate it when you want it on and is unlikely to be activated while carrying it in your pocket or clipped to your belt. Speaking of the clip, it holds strong and doesn't tear up your clothing. Essentially, the light should be there when you reach for it.

The body of the light has the customary exact machining of Sofirn with good knurling on the tube and tail as well as precision, smooth, anodized square-cut threads.

The button-top battery is stated to hold 2,200 mAh and I'll agree with that but one metric I actually made was that the internal resistance is around 79 mOhms per my Miboxer C4-12. I also measured the current using this cell and it settled down to 1.6 amps. For contrast, a fully charged Samsung 30Q pumped 1.96A through the SC31 and at 3.8V, the current was measured at 1.48A.

The micro USB cable conveyed .39-.41A whilst charging the light. This was measured with this: USB Voltage and Current Meter

A little data:

Phone app lux meter, ceiling bounce at 1.7 m ( I need a better app!! ):

I played with some online calculators and came up with about 560 lumens although 1.96A should be higher. I found djozz's test:

To wrap this review up:


  1. size;

  2. USB rechargeable;

  3. side e-switch;

  4. tail cap lock out;

  5. knurling;

  6. typical but good USB port cover.

Wanted change:

  1. Nichia 3-4K tint emitter;

  2. moon/firefly mode.

Back in July, there was a post called “What one light for Mom?” and I think this light is a great candidate among others mentioned there. Of course, this light would be good for anyone who just could use a quality light. I like the breathing switch light that would assist with someone locating the light on their nightstand at night and that it has mode memory. The larger switch may be good for persons with issues such as arthritis and other age-related ailments.

Thank you for reading!

For the runtime graph above, the termination voltage was 3.5V. The light was run on high continuously and it got pretty hot. I think the mid-graph output bump is from a cool down with the voltage drop.

Nice review. One is on my way. I like simplicity, big backlit button and direct USB charging. Perfect gift.

Thank you! My first 'official' review. It's a skill in progress .

Sofirn is my favorite brand. Just as good as Convoy, Astrolux and other middle class brands. Quality and cheap flashlights, great customer service. I have 12 flashlights from Sofirn and three on the way. Sofirn C8A XP-L2, Sofirn C8T XP-L2 HI, Sofirn C8F triple XP-L2, Sofirn SP10B red+blue, Sofirn SF02 Red, Sofirn SP32A, Sofirn SP30A, Sofirn SF10, Sofirn SF36, Sofirn SF13, Sofirn SP33. It’s sickness :smiling_imp: :person_facepalming:

That is pretty much my list, plus or minus a light or two.I count my BLF Q8 and the Sofirn Q8 also. Sofirn has been great for me . As you said , CS, quality and economy. :+1:

Thanks for your review. :+1:

I measured the two SC31 I have using my calibrated Texas_Ace Lumen Sphere to 446 lumens and 469 lumens slightly after turn-on using fully charged Sony VTC6 batteries. The included Sofirn batteries measure less lumens. This is lower than the 600 lumen spec. Sofirn has been conservative with their lumen specs on some of their lights like the 18650 C8F but over rated some of their other lights like this one and the 21700 C8F. But Sofirn in general is more honest than 95% of the bargain flashlight brands out there that inflate their lumen ratings to couple hundred percent of actual.

I swapped in the SST-20-w 95CRI on 16mm mcpcb from Kaidomain and the light is beautiful. I gave them away as gifts. However, I like the SP30A with the two switch design much better but the SP30A wire location is not compatible with the typical 16mm mcpcb and I don’t reflow emitters myself. I might buy a few more SC31 just because it is so easy to swap in MCPCBs.

Thank you for adding to this review!

I have Samsung 20Rs and the 30Qs as well as a VTC5 so those are what I use for hi-drain. However, I tested an SC31 that only hit 1.4A but it wasn't mine.

I looked at those Luminus data sheets and they are a sub-1000 lumen emitter but I understand the draw to high CRI. Frankly, I've never strayed beyond Cree and Nichia but I think I'll try the SSTs out. Perhaps, (hint, hint) Sofirn will make a new offering in the SC31!

I also have some dual switch lights but what I really like about single E-switch lights is locking out the light by a tail cap turn. No switch to burn out, more quiet and potentially better current flow.