The Road Master photochromic convertable features shatter-resistant polycarbonate lenses that darken in the sun, and lighten indoors, in about 2-3 minutes.The lens transmission allows 87%of light through indoors & allows 47% of light through outdoors. Removable soft foam padding on the upper portion of the frame adds comfort for extended periods of wear, and filters dust. This convertible uses removable temples for a quick change between sunglasses and goggles.