Hello Face L6 Pro LED Mask, 720 Diodes, 630nm Red and 850nm Near-Infrared

The one device on this store that publishes the numbers the studies used: 630 nm red and 850 nm near-infrared, 720 diodes, in a skin-friendly fabric wrap that sits against the face and neck rather than floating above it.

This is the anchor. If you are going to buy one light device and keep it for years, buy the one whose specification you can check.