The basic T-Zone LED Device uses white LEDs with cover colours. There are three replacement LED plates available for the Device. The plate LEDs use the wavelength, 470nm, 660nm or 880nm. LED Device sold separately.
880nm is infrared light. It may appear in the dark as red.
Infrared light – Deep penetrating light at 880nm penetrates to a depth of about 30-40 mm, which makes it effective for internal problems. The infrared light can be used for 24-36 minutes, 2-3 times per week.
References
The NASA Light-Emitting Diode Medical Program -Progress in Space Flight and Terrestrial Applications:
http://content.lib.utah.edu/utils/getfile/collection/uspace/id/2713/filename/4336.pdf
