Our swimming is soft food grade liquid silicone skirt &strap, providing extreme comfortable using . Our diving used film avoid fog appear on the inside lens with exhalation from nose, making clear under water. Our snorkeling that blocks out harmful , delivers a glare-free view of the underwater world. Adjustable for head straps fit virtually any face shape and heads in different sizes. should help you , not obstruct part of your view. enjoy all the underwater scenery clearly.