They need to tool up for some other metals!
Got them. They are perfectly acceptable on low. Still going to put a 45 degree optic on it to make it dimmer. It really is hard to judge monochromatic lights based on pictures or numbers.
If we have a chance for a lower low and a higher highā¦any chance we could get far red (720 nm)? 
A far red LED would not be able to make a useful amount of light. Probably 1 lumen or less.
SST-10-FR is 730nm. Human eye is about 117x less sensitive to 730nm compared to 660nm. Not sure what LEDs are available at 720nm, but eye sensitivity isnāt much better at 720nm compared to 730nm.
Iām just checking with Sofirn if itās feasible, reasonable and cost-effective to revive C01 using a 5mm EPIGAP EOLD-670-524 LED with 670nm.
https://www.epigap-optronic.de/tl_files/frontend/epigap/Datenblaetter/LED%20VIS/EOLD-670-524.pdf
However, costs could be insane for a small batch of these lights. Maybe I should contact them to get a quotation. :-D
No way, sorry.
I could imagine they have a plan like this in the drawer but materials like copper, titanium or brass are rather expensive and require different tools for machining. I wouldnāt mind to see a nice C01S in mokume gane for $ 80.00 :-D
I made some suggestions to Sofirn to lower the low mode for better preservation of the night vision and to reduce brightness on medium mode as Djozz mentioned before as it is too close to high mode. I also suggested trying to raise the current on high mode a bit more as SST20-DR can sustain higher currents than XP-E2 photo red. Not too much of course for a small light like C01R but maybe itās worth trying. ;-)
Far Red is probably not worth it as most people will barely see any light coming out of the front. I suppose the reasonable limit is 690nm (for medical/scientific purposes like here https://budgetlightforum.com/t/-/62550).
Iām in for longer wavelengths if price is right. Else I would say a different optics and a lower low would be a huge step forward. But bear in mind that the floody option significantly reduces brightness already. Weāre not talking about low reduced by a magnitude.
Concerning longer wavelengths:
IMHO, it's quite a risk for a manufacturer to start a series production of these exotic flashlights, even if their MPQ is 250 pcs only. The smaller the MPQ is, the higher costs per unit eventually get, which again leads to less margin in selling for a reasonable price to the customer. If we now pursue to get a C01R with 730nm, chances are big that many customers will feel screwed after buying and using the light as there's barely any light to see even on high mode. A light like this could be useful for medical or scientific purposes for sure but that's a whole different category. I have no reliable, scientifically proven source right now but word of mouth is that high radiation not only of short wavelengths (x-ray, UV-C, UV-B, UV-A and even blue light) but also of long wavelengths (far red - infrared) can be harmful to the human eye.
Concerning some tweaks in C01R:
I didn't want Sofirn to reduce brightness settings by a magnitude but some gentle reductions to improve mode spacing. A lower low might end up in a great firefly mode using the "honeycomb" optic or anything more frosty/hazy/milky...whatever. :-)
Marginally scientific low runtime test:
Freshly charged ~10 year old Eneloop AAA: 55h 10m
Shutoff voltage: unmeasured
Freshly charged ~2 year old Amazon ā750mAhā rechargeable AAA: 57h 0m
Shutoff voltage: 0.835V
Anybody else in the US still waiting for their light to emerge from the e-commerce black hole that is Newgistics?
Gave up on receiving mine. The post office does not deliver to homes up here in the mountains, only to PO Boxes. So I always put both addresses since UPS and FedEx bring to houses. But companies change things. First they did not include the PO Box and Lin contacted me. I gave her the PO Box and they tried again, but that was undeliverable too for some reason. So no go. Other things were delivered to me from them and other companies. Life in the country is so good I do not mind an occasional glitch.
Iāve been abroad with work and only just got my hands on my C01R.
Light output is great, the wavelength is noticibly deeper than other red leds Iāve got, when ceiling bounced on high, the colour reminds me of film scenes in submarines or photo dark rooms.
Re. Brightness, yes the low could be tad lower but itās not a deal breaker for me.
I ordered the hard plastic AAA diffuser at the same time as the C01R, on medium or high this will make a great 360 degree light to clip onto a backpack when cycling.
Just got mine. Love it but hotspot is kinda anoying so i took a piece of Scotchbrite and āpolishedā lens a bit. Result is amazing, beam is uniform without hotspot and artifacts.
The holdup for mine has definitely been Newgistics. My light was finally handed off to the post office yesterday, and is out for delivery today. It only took a week or so for it to get to the US. Newgistics and their āshipping partnerā had it for over a month! Iām hoping that yours is just in the same situation, and will get to you soon.
12000 km in 60 days, 200 km per day, still faster than walking or swimming from China 
So set on medium, held at elbow length so it illuminates both eyes, viewed for three minutes through closed eyes.
I think thatās roughly the prescription. Time wll tell if my vision improves.
With all the talk about 670nm deep red led helps eyesight @ 670nm deep red led helps eyesight
Using a 670nm would lead me to get another one or two
Maybe add some blue anodizing for health
Cheers
OS
This is already the light you seek. This LED is 650-670 according to data sheet. The next ādeeperā red (called Far Red) is 720-740 and barely visible. I doubt it would sell very well.
We already brought up alternative emitters in the C01 thread, but Barry said they are planning to just do one emitter to keep the cost low.
https://budgetlightforum.com/t/-/51879/2900
He did not confirm if a host version will be made, but djozz was previously under the impression this would happen if a new C01 batch is made. A host would be very easy to solder your own 5mm LED into.
Even if there is no host, it will be unpotted.
There is no prescription. Some initial research with small numbers of participants indicates there is probably an effect. Confirming this as known beneficial treatment without significant side effects to FDA standards will requirement significantly more testing. The risk does seem very low, so Iām hardly going to discourage it, but be careful about overstating what is known at this time.
EPIGAP charges considerable prices plus shipping fees for their 670nm 5mm LED. Consequently, this idea is not viable for a small batch of C01 lights. :-( Still, you may feel free to manually swap the emitter in an existing C01 light.