SunSensors™ is photochromic lenses

SunSensors™ is photochromic lenses, often called auto-lenses. It darkens as a sunglasses tint when exposed to sunlight, or U/V ultraviolet (depending on the UV light exposure in your environment), and automatically return to a clear state when indoors, away from U/V light. With IN-MASS technology from SunSensors™, which adds up to 400 nm of UV protection and adjusts the color into the lens material. So there is no need to worry about coat peeling, even with peeling marks or scratches on the lenses surface, the color density changing will remain the same performance. Once the lenses exposed to sunlight, the lenses will be darkened 50-60%, similar to sunglasses that preventing glare from sunlight. On the other hand, once the lenses indoor, it will quickly return to transparency and comfort. Eliminate having to switch between sunglasses and regular eyeglasses by enjoying a single pair of eyeglasses for both indoors and outdoors as SunSensors™ all-day comfort anytime and anywhere.