The photochromic lenses of the John Doe Ironhead sunglasses with the self-tint ability offer excellent visibility in any conditions. Under UV-light they go from clear to light/dark gray and vice-versa within seconds, depending on the intensity. Durable frame construction and a modern design round off the whole package. Features: • Polarized photochromic lenses • Excellent comfort • Tint from light to dark gray • Shatterproof lens design • UV-400 protection