Scubapro Crystal VU Dive Mask A large single lens plus seamless side windows equals an expansive view under water. The double-sealed silicone skirt offers a seal that is both comfortable and watertight. Swivel buckles allow for the perfect fit and an exclusive paint process lets you dive with style. Features: Patented tempered glass single-lens design with side windows creates a panoramic field of vision. Double-sealing skirt is comfortable against the skin and keeps water out. Convenient swivel buckles allow for a snug fit and ease of clearing.