This is the Bare Sport Duo B Low Volume Scuba Diving Mask Features: Twin lens design. Revolutionary push-button buckle allows for easy, quick strap adjustment. Unique flexible buckle attachment swivels with facial movements and absorbs shock, preventing buckle breakage when mask is bumped. Low volume for easy clearing and wider field of vision . Super lightweight. Highest quality tempered glass lens. Black double flanged silicone skirt. Classic two window design with a soft and supple double-flanged silicone skirt.