nice 3 mode Red light! recommended
on my meter w AAA Eneloop, modes are
0.3
7
43 lumens (meter reads lower than actual at this level with this TiR)
I like that there is a sublumen level, and I like the mode spacing
Thanks for the nice comparison and for measuring the output. :-)
Did you actually get this from Sofirn, or is this a modded C01R that was originally sold with XP-E2 Photo Red 660nm? If so, you MUST absolutely disclose that in your review, otherwise this review is misleading Sofirn customers and unfair to Sofirn. It might be nothing like the final product.
thanks for letting me know that the light I got was old stock w 660nm XP-E2. I like it!
I don’t know for certain but you could try subscribing for their newsletter on sofirnlight.com. That’s the place where Sofirn usually starts selling their brand new items first. Moreover, I will try my best to keep everyone updated on my C01R thread as soon as the (pre-order) sale of the second batch becomes available.
thank you Noir 
Has anyone experienced mode changing stuck in low?
It will only switch modes if twisted down tightly, too snug for practical use
Cleaned off all copper contacts and threads, and no change in function
I work nights as security… It’s a shame this light cannot be programmed for middle mode only
Low beam (0.5 lms) is useless outdoors for reading under wet conditions. And, high beam is ridiculous, way too many lumens for practical use imo
SST-20 deep red 660nm this is a perfect wavelength color…
Only problem now is finding a suitable flashlight (or drop-in) to make it work properly for me
Hmm. I haven’t run into that problem myself, but it certainly sounds like a contact issue.
You’ve tried cleaning the head, but perhaps the contact inside the body is the culprit? It may have some lubricating grease on it that needs to be cleaned off.
If all else fails you can try connecting a battery directly to the head with wires, and see if the issue is reproducible. If so, then it’d be a driver issue rather than a contact issue.
imo the issue is caused by the pcb, which is not potted on the C01R, sinking into the head
my fix would be to stuff a little .1mm thick shim, I happen to have thermal tape, under the contact pad ears, with the goal of lifting the contact pads on the head, so they reach the shelf in the body:
fwiw, my C01R, picutred, works fine. I do not have any issues changing modes, it does not need to be overtightened.
Good fix. Someone tell Sofirn about this please.
Look at how much higher sits the center (+) terminal on the red one—it’s a totally different design. There is a potting on both versions, just different colored materials, to keep the pcb from contacting the side walls. If anything the protruding center terminal is fighting against you—file it down or change out the bottom spring. It only takes 1/8th of a turn to switch ON/OFF.
I tested the driver function using battery and leads. Mode switching is normal after a dozen or so trials
So, as Jon has pointed out, the culprit is pill has sunk lower on one side tilting driver creating uneven contacts on body shelf
I also hope someone at Sofirn is listening. Start potting these C01R and/or at least pay attention to finished assembled product QC
Inexpensive as they are, I’ve still invested over sixty bucks on aaa lights, C01, C01R, C01S, etc.
It’s very disappointing to have pile of flashlight parts that don’t work
Mr Lan Lee from Sofirn CS was very understanding, after explaining the assembly issue they’re sending a replacement C01R
So, Kudos to Sofirn!
Ms. 
Not visited this site for many weeks, and I almost missed this! I’ve been after a 660nm light for some years and never found one. All red lights seem to be 625nm.
Then I find out Sofirn have brought out not only a 3-mode 660nm, but also a 670nm version is available. I’ve ordered both versions because they seem to be selling them off at reduced price. So maybe it is best I only found out about them late, because otherwise I’d probably have paid more.
The only feature I am not keen on is the twisty head on/off. I prefer a tail button. But I’m really pleased to find these, I hope they are as advertised. Has anyone confirmed the wavelengths independently?
How many version does this C01R have? I don’t know which version I have.
There seem to be at least two available on the Sofirn website:
1. 3-mode 660 nm
2. 1-mode 670 nm
Looking at this forum, it looks like additional versions have been available in the past.
The 670nm C01 is much less powerful.
there have been two different versions marked C01R
1. the first version is 660nm uses xp-e2
2. the second version, is 660nm also, but the LED is SST-20
I dont know how to tell them visually apart, both are the same red beam color, 660nm.
If you ordered in November it is most likely SST-20, if you bought it before that it is probably xp-e2
both versions use the same 3 mode driver that can be set up as HiMedLo, or LoMedHi, mode sequence.
Your actual invoice could help answer which LED version you bought.
Non C01R models:
the 670nm version is marked C01 and has only one mode. There are also other versions of C01, that use 3400k LEDs, single mode. And in the past there were C01 with 3200k and 5600k LEDs, also single mode.
Lastly there is a C01S, which is a two mode light w 4000k SST-20. Originally released as HiLo, present version is LoHi mode sequence.
Thanks guys. I ordered it before November. Probably it’s xp e2.