This mask was designed specifically for deep sea diving, with innovative features that place it at the top of its category. The special reduced skirt, complete with a small seal ring, sticks like a suction cup to the face, leaving minimum air space inside the mask, which make compensation extremely easy, taking very little air from the lungs. The lens-eye distance is the absolute smallest on the market and guarantees, even with small diameter lenses, excellent visibility in all directions. The two optic glass lenses are thicker than the standard to allow a special safety mould. The strap comes with instantly adjusting buckles for an easy and precise fit