Glenn Jeffrey has tested this light and says it is ok. https://eyecharger.com.au/. Looks to be about $100 US. A very high price in my opinion. They told me it puts out 15-20mw/cm2. I want to do this soon and I might just spend the money to get it done with. As discussed in a previous long thread on this subject 650-700 leds were used. (?) The intensity tested was 8-40 mW/cm2 assumedly at the cornea. As far as I can tell a meter to measure mW/cm2 at 670 can be had for under $200. The lengthy previous discussion on this topic seemed to not produce a cheap red flashlight the human race could use. If someone built a similar device and tested it with a mW/cm2 meter and put an appropriate spacer tube and has it for sale please let me know. This is not brain surgery but
many people selling devices for sale saying it’s for the eyes couldn’t be bothered to put out a properly designed device. Logan
I have an Emisar D4V2 with 660nm SST-20 emitters. For a spacer I cut a short piece of pvc pipe. When I use it for my eyes, I just use it on its moonlight mode (lowest setting).
I have been using red light on my eyes, nose, ears and throat, as well as on bruises and sore muscles, since I learned about it here.
I dont use a special distance, I dont use a tube… I just close my eyes, and shine the light, at about 10 lumens, towards my eyes from 10" away.
for nostrils, ears, mouth, and injuries, I put the light in contact or very close, to the target.
I dont do it for long periods… just a few seconds is enough to wake up the mitochondria in the morning. IF we were spending more time in natural sunlight, we would not be needing to use Red light as a supplement.
My understanding is that red light is very safe, it does not create heat when shined on the body, even with the light directly touching the skin.
I dont think there is a specific magic distance nor intensity for red light therapy for the Retina. Red light is just good for us… I dont use crazy bright, just eough to be noticeable thru closed eyelids.
I use much dimmer red light, than 10am morning sunlight shining on my closed eyes… Thats my reference for a safe limit.
imo any 660nm Red Light can be used therapeutically… It does not need to be exactly 670nm, just because that is what was used in one study… In fact, I also use 730nm red light… nothing bad has happened.
Whether or not my eyes have improved, I cant say… Its not like there has been a noticeable change in my eyes. I still need to wear glasses to read…
I do it because I think its good for me, and at least seems to do no harm, but I dont expect any miracles.
That’s nice jon but I and many others would like to replicate the dose used in the science, the method of stimulation and dose used in the science which I believe was with opened eyes and hopefully get the improvement shown in the science which in my opinion approaches magical.
totally up to you how you choose to use Red Light… I think you already found a suitable product… it is just a matter of paying the price
I hope it produces magical results for you 
I don’t’ think anyone here has tested any home built red lights using a mW/cm2 meter. That being said, the Luminous SST-20 Deep Red and the Cree XP-E2 Deep Red which both are 660nm are totally sufficient for this purpous. Glenn also posted here on this forum that 670nm is just what they happened to use and test with, but it doesn’t mean that it is the end all perfect wavelength. Also, 660nm leds don’t just emit that one specific wavelength, there is a curve so it still puts out plenty of 670nm if that is what you desire. But it seems like you have already made up your mind what you are willing to buy, so if you decide to get the one you linked to, use it in good health.