Flexible Silicone for Leak-Proof, Comfort Seal: Skirt and mask strap come in soft, supple silicone, which molds the dive mask to the shape of your face for a much more comfortable fit and watertight seal. Your snorkeling or scuba diving experience will be much more enjoyable with no more leaks or discomfort. Tempered-Glass Lens for Safety: Forget the other snorkel gear that use flimsy plastic lenses! Our single lens scuba mask uses quality tempered glass, which resists scratching and shattering giving you peace of mind and a much better experience. Convenient Buckle for Easy Adjustment: Simply pull the straps to desired fit and the buckles will hold the straps securely in place. Presto: customized comfort for any diver. Snorkeling Gear for Adults Rugged Enough for Scuba Diving: Thanks to its sturdy construction, your mask can stand up to all kinds of wear - from snorkeling in the pool water to deep-sea scuba diving to safe recreational scuba diver depth limits. One-Piece Lens: A snorkel mask should help you see better, not obstruct part of your view. Now you can enjoy all the underwater scenery clearly.