Cressi Scuba Diving Masks with Inclined Tear Drop Lenses for More Downward Visibility, Big Eyes EvolutionThis revolutionary mask is made of High Seal Silicone, a material that offers unprecedented comfort and a perfect seal ideal for scuba diving, snorkeling, and freediving. The raked lenses, with their inverted drop shape (Cressi patent), are quite small and are inclined as close to the eyes as possible to improve the downward visibility. The lenses may be replaced with prescription optical lenses ideal for myopic. The frame uses the exclusive patented