AuKvi Red Light LED Flashlight Zoombale Red Hunting Light Torch,Single Mode Long Range Red LED Red Light, Waterproof Red flashlight Torch Best for Astronomy, Aviation, Night Observation,etc

I used a spectrometer in our shop to check the 2 units I got. Both have a peak wavelength of 668-669nm with a central wavelength closer to 665nm. That should be good for LLLT at 670nm. In the chart, the green line is 670nm.I was also able to measure the output power at about 200mW. You can use that and the fraction of the output that's actually entering your eye to calculate the dosage. I hold it at arms length set for the largest spot and keep my eye's closed and it's bright but not uncomfortable. The higher power is good for deep tissue LLLT. I'm using them at full power on a trick knee. Too early to say whether it's helping though.

Decent product for the price. Not the brightest or longest reaching beam of light but will get you through in a pinch. I attached it to my shotgun for a gun light and use my foxpro light as a scan light. This light will do the job.

The build quality of this flashlight is very good. It is easy to turn on/off and the zoom function is working very nice - you can get wide or narrow light flash.However, to serious stargazing under moonless skies it is simply too bright.I have to cover it, like in the picture, to dimm it enough to use for stargazing. This is why it is only 4 stars and not 5.

Works great

Product is solid and well built. Light is very bright and focused. Great for checking outside.