The Seashadow is the ideal choice for smaller faces... but it’s still BIG on performance. The Seashadow features a silicone skirt and fully adjustable headstrap and is one of the few masks available with a choice of either fully glazed CR39 plastic lenses or bonded, tempered glass lenses. The prescription range for CR39 lenses is up to +/- 3.00 sph. Opp. Cyl. to 2.00 Bifocal ( reading Add ) is not available with this mask. Please note, the Seashadow is one of the lowest volume masks available today, making it unsuitable for high prescriptions.