Cylindrical Lenses: - Rossignol cylindrical lenses are made from polycarbonate (PC) sheets which are cut out, shaped and assembled with the internal lens. This means that the lens is flat, with its eventual shape being provided by the frame.Fog Control: - Fog Control Technology provides an anti fog coating on the screen added to a perfect venting that totally avoid any fog issues.Specifications: - Usage: All Mountain- Visible Light Transmission: 0.27Frame: - Shape: Cylindrical