A two-lens mask, complete with patented Cardanic Joint Buckles. A stainless steel (AISI 316) anti-torsion bar has been integrated into the frame structure for maximum dimensional stability and lens planarity. This optimizes visibility by eliminating distortion. 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. Glass: 4mm tempered flat, Buckles: Cardanic Joint Buckles, Skirt: Silicone, Black, Color: Black