BLF has conspired yet again to design a light that it’s impossible to not want.  This time it’s a tiny AAA light, made by Sofirn, with a Yuji emitter, and very high CRI.  The single mode is very low output, but with very long runtimes, and two temperatures available.  It’s also very inexpensive!

Official Specs and Features

Here’s a link to the official product page.


There are two versions of this diminutive light.  The bodies are the same, but it’s available in 5600K (Cool White) (ok.  they call it “Neutral White”) and 3200K (Warm White).  I have here one NW, and three WW.

Also available is a red body, and a blue body version!


Initially there was a group buy price, but the price currently is $7.55 for either version.

Short Review

I love these little lights.  I wish I had bought more (and probably will).  These are fantastic to give to a child for nighttime reading, or reading/navigating inside a tent or the like.  I completely support you buying at least one of each!!  (I don’t even get anything from you buying them!)

I’m pleased to have both, and to be able to see the different Yuji tint in person.

Long Review

The Big Table

Sofirn C01
Emitter: High 94 CRI Yuji LED (NW (5600K))
Price in USD at publication time: $7.55
Cell: AAA
Turbo Runtime High Runtime
Switch Type: Twisty
On-Board Charging? No
Claimed Lumens (lm) 8
Measured Lumens (at 30s) ~
Claimed Throw (m) 6
Candela (Calculated) in cd (at 30s) 11lux @ 1.075m = 13cd
Throw (Calculated) (m) 7.1 (118.3% of claim)*
All my Sofirn reviews!


Sofirn C01
Emitter: High 94 CRI Yuji LED (WW (3200K))
Price in USD at publication time: $7.55
Cell: AAA
Turbo Runtime High Runtime
Switch Type: Twisty
On-Board Charging? No
Claimed Lumens (lm) 6
Measured Lumens (at 30s) ~
Claimed Throw (m) 5
Candela (Calculated) in cd (at 30s) 6lux @ 1.05m = 7cd
Throw (Calculated) (m) 5.1 (102% of claim)*
All my Sofirn reviews!
  • Standard measurement disclaimer:  I am an amateur flashlight reviewer.  I don’t have $10,000 or even $1,000 worth of testing equipment.  I test output and such in PVC tubes!!  Please consider claims within 10% of what I measure to be perfectly reasonable (accurate, even).

What’s Included

  • Sofirn C01 Flashlight
  • Spare o-rings (2)
  • Split ring
  • Manual

Package and Manual

The C01 ships in a flap closure cardboard box.  Nothing special, but easily recyclable and no printing on the box.  Inside, the light is in a bubble sleeve.

The manual is surprisingly thorough for a light of this… price.  But all the needed info is there, in a 3 page manual.  There are two other languages, too.

Build Quality and Disassembly

These are not the highest build quality lights I’ve used.  They certainly get the job done, and the components seem well secured.  But for example, the finish, and in-hand feel, is on part with a $8 light.  That’s not a problem; this is an $8 light.

There is no external difference between the WW and NW.

The body is full of knurling.  The head too has adequate knurling for good grip while twisting.  The threads aren’t tight, so one handed operation is easy.

The tailcap has a lot going on, but will tailstand easily.  Note the two holes.  One of those is for a 5mm magnet, and one is for a tritium vial.

The tail end has a spring.  The head doesn’t have a spring, or even an actual button – it’s just a little brass pad on the mcpcb.

The threads are extremely smooth.  They’re fine threads, very lightly lubed, and anodized.  In the photo above and below you can see the little contact pads that meet the unanodized section on the body tube.

Size and Comps

71.1mm (length)
14.5mm (head diameter)
Weight: 16 gram (without cell)

Here are some comparable lights.  The Olight i3E EOS is a twisty single mode light, and much smaller than the C01.  (I’d love to see the C01 in i3E format!!).  Then the titanium Tool AAA, and finally the BLF-348.  The 348 sure is a long AAA light!

Retention and Carry

A pocket clip is installed from the factory.  It’s a friction fit clip and allows for fairly deep carry.  It can go on the head or tail portion of the body, so bezel up or down carry is an option.

Another option is to put a 5mm magnet in the magnet hole on the tail.  A magnet is not included (and unfortunately I only have 6mm magnets. At first I wanted this to be a threaded hole for a tripod, but a magnet is probably a better choice.

Power and Runtime

Power for the C01 is an AAA sized cell.  I used NiMH, but alkaline primaries would work too.  Liion (10440) is not supported- the voltage would be too high.  As there is just one mode, and very low current, NiMH is perfect.

The NW is claimed to have a much higher output than the WW version.  As such, I’ve scaled the WW runtime to the NW’s output.  The output is too low for my normal home-calibrated system, so these are just relative outputs, not actual lumens.  Though I can say that’s probably better for these lights, since you’ll probably them precisely because their output is low.

Output for the both is extremely stable (variations along the way more than likely due to sampling issues, and not output variations).  The light holds at approximately 100% for almost 11 hours before dropping off “fairly quickly” over the course of another 2 hours or so.  The output never stops, too.  Even when I was reading well below 5% of initial, the light was on.  So there isn’t LVP, but that’s not usually necessarily in NiMH lights.

And here’s the WW runtime – again, scaled where “100%” would be the full output of the NW version.  Basically it means that the WW is ~70% the brightness of the NW (which is exactly what the specs claim).

User Interface and Operation

Here’s a UI table!

State Action Result
Off Twist On
On Twist Off

Hope that’s not too complicated of a UI….

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
On NW – 8 35h (probably for primary cell) ~8 0.02
On WW – 6 35h (probably for primary cell) ~6 0.02

LED and Beam

Left is the WW version, right is NW.  The NW version has a more “yellow” center, and the WW has a more “yellow white” center.  For more clarity, see the picture below, and remember I bought three WW and one NW.

The interesting thing about these little lights is the emitter.  They’re 5mm emitters, which can’t handle much current, but have very high CRI (94).  Here are the specifics.

Neutral White Version (YJ-BC-F5-56-60 5600K)
Warm White Version (YJ-BC-F5-32-60 3200K)

Also, there is no lens!  The reflector is made out of the aluminum of the body, and the dome of the Yuji is exposed.  That’s fairly unique setup, and makes for a very floody beam!

Just to give you a sense of the brightness of these two lights:  Below the two shots are in the normal setup, and the beam isn’t even visible.

So against the door, here’s a better look.

And this is the C01’s compared to each other:

The output seen below is at the end of a 12 hour runtime.  Still visible, but not really all that usable.

Tint vs BLF-348 (Killzone 219b version)


Random Comparisons and Competitive Options….

I don’t think there’s anything else that uses these Yuji emitters.  But these!!


What I like

  • High CRI
  • Low cost
  • Simple UI
  • WW and NW options

What I don’t like

  • Wish there was a trit and magnet installed option


  • This light was provided by myself for review. I was not paid to write this review.
  • This content originally appeared at  Please visit there for the best experience!
  • Whether or not I have a coupon for this light, I do have a bunch of coupons!!  Have a look at my spreadsheet for those coupons. It’s possible to subscribe and get notifications when the sheet is edited!!

1 thought on “Sofirn C01 Single Mode, Yuji High CRI, AAA Flashlight Review”

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