Professional divers have come to us for years. Now sport divers, photographers and snorkelers are discovering the benefits of clear underwater vision. Prescription Dive Masks custom makes each lens for your prescription, using your personal measurements for optimum vision. Your lens is created specifically for the mask you select. The lens size is kept as large as possible, to give divers a full field of vision. Then it is bonded to the glass face plate with optically clear adhesive that never comes off.