Speedo's #1 selling kids' goggle! The Relay's have a soft neoprene gaskets, latex head strap, and shatter-resistant polycarbonate lens that is 20 times stronger than glass, now using the high technology materials underwater as used in outer space GE Lexan_ polycarbonate. Goggles feature T-slot system for quick and easy head strap adjustment, and have an adjustable nose seal.