buckle closure thermoplastic polyurethane frame anti-fog coating coating[professional ventilation]-designed to reduce fogging and optimizes the flowing air over the inside of the lens.ski goggles provide smooth air-flow system which brings fresh air and exhaust moisture quickly and effectively. [performance double lens]anti-fog,impact resistance,full face real revo mirror coating reflective lens,100% uv protection,more solid durable than others ski goggles.the inner lens made by italy with pro long-lasting anti fog performance materials,working with ventilation system. no fogging up when skiing or snowboarding. spherical lens and frameless design create a super wide hd vision..syi