Aqua Lung Scuba Snorkeling Dive Mask Dry Snorkel Set Patented Dry valve stops water from entering the snorkel eliminating the need for clearing the snorkel Large bore contoured barrel for unrestricted breathing Shatterproof, tempered glass lenses suitable for diving and snorkeling meet ANSI standards. High-grade silicone material allows the facial skirt to flex and naturally mold around facial contours for a leak-free seal. Wide headpiece on silicone strap conforms to the user's head to ensure a comfortable, secure fit.