PURE SILICONE - FDA regulation compliant. (Rubber articles intended for repeated use / 21 CFR 177.2600) TUSA Sport use pure silicone for the snorkel mouth-piece and mask skirt. CLEARVU TEMPERED GLASS lenses provide superior clarity, color, transmission of light and safety over standard glass. EZ STRAP and BUCKLE SYSTEM - Allows masks to be quickly and easily adjusted with minimal effort. Allowing for a precise fit and ease of removal when necessary. HIGH FLOW PURGE VALVE - A large diameter purge valve for simple, quick clearing, reducing the amount of water remaining in the mouth-piece. HYPERDRY ELITE - DRY TOP - The latest innovation in dry snorkel technology utilizing an independent high buoyancy float for superior dry performance. This keeps the snorkel completely dry by quickly and efficiently closing the tube opening.