Aqua Lung Look HD Scuba Diving Mask The frame is rugged because it is made from innovative techno-polymers reinforced with inorganic fibers. A stainless steel bar has been integrated into the frame to eliminate torsion and keep lens in the same plane. Advanced Fit Technology(AFT) uses bands of different textures around the edge of the skirt to provide a superior seal against the face Cardanic joint buckles swivel up and down, in and out for optimal fit and comfort 4mm tempered flat glass