Light changing lens technology! Transitions lenses contain special patented photochromic dyes that cause the lens to activate, or darken, when exposed to ultraviolet rays from sunlight. When the UV light diminishes, the lenses fade back to their clear state... As light conditions change, the lenses adjust quickly to provide the appropriate level of tint. The ideal lenses if you are consistently going inside and outside for work. All SafeStyle lenses are made from 100% recyclable UV400 shatterproof polycarbonate, blocking 99.9% of UVA/UVB with a super-hard anti-scratch coating.