I am just looking at the extraordinarily high price of the Vielight 810 Infrared device ($499) and the Vielight 633 Red device ($299). Do you know that you can buy the red LEDs or infrared LEDs contained in these Vielight devices for less than $1 !? If you look here on eBay, you will see 9 volt red LEDs for sale for less than $1 each. And if you look here on eBay, you see 9 volt infrared LEDs for sale for a similar price. All you have to do is connect one of these LEDs bought on eBay to a regular 9 volt PP3 battery, and you can create a home-made unit that will work just the same as a Vielight, but at a tiny fraction of the cost. You can even find LED lights on eBay already fitted with PP3 battery clips, that clip straight onto a 9 volt battery. A cheap home-made unit for a few dollars should allow people to experiment with intranasal light therapy without paying out $hundreds. Note that the precise wavelength of light of the LED does not matter much. I have seen various research papers looking at the biological effects of red and infrared light, and there is no one magic wavelength. Red light does tend to have slightly different effects compared to infrared light, but the precise wavelength of the light is not that important. So the Vielight 633 unit uses a red LED pumping out light at a wavelength of 633 nm, but any red LED with a wavelength in the range of say 620 nm to 660 nm should work equally well. Equally, for the Vielight 810 Infrared unit which outputs invisible infrared light at a wavelength of 810 nm, any infrared LED with a similar wavelength (such as 850 nm) should work equally well. I used to build electronic devices as a kid, so I know one or two things about electronic components.