Tusa Visio Uno. The M-110s single window design offers great visibility, reduced internal volume and enhanced comfort while incorporating several Tusa patented mask technologies such as a 3-D strap, Round-Edge skirt and a skirt mounted Quick-Adjust Buckle System. Additionally, the M-110 design is available in a special edition enhanced with optical glass, AR/UV coating and a chrome frame, the M-110SQB-CR Visio Pro. Features:- Low profile, single window teardrop design. - Enhanced field-of-view over 2-window masks. - Skirt mounted Quick-Adjust Buckle System. - Round-edge skirt for maximum fit and comfort. - 3-D strap for ideal anatomical fit.