Open Box Tusa Visio Tri-Ex Mask (M-31)The TUSA M 31 Visio Tri Ex mask is a revolutionary new 3 window design offering an ultra wide; panoramic view. This amazingly wide viewing angle is achieved by the incorporation of domed side windows and the significant reduction of frame structure around the lenses, increasing the field of vision by dramatically over traditional masks. The M 31 mask gently conforms to the contours of your face. Constructed with crystal silicone, this mask has been