Cressi Evo Evolution Crystal Dive Mask, Includes Hard Mask Box (NEW 2010) Skirt in High Seal silicone | Special structure of the skirt has differentiated rigidity Very narrow headband in three materials, invisible when the mask is worn Instantly adjustable buckles that are joined to the headband with an indestructible elastic element Downward visibility is increased by 25% compared to the Matrix Minimum internal volume