Made of silicone rubber for better durability and will hold its shape even in extreme heat and cold. The double sealing flange provides an improved face-to-mask seal and a deep chin pocket provides a better, more comfortable fit. The replaceable polycarbonate lens offers a wider, distortion-free viewing area with an anti-fog, anti-scratch coating. The unique "over the shoulder" hose design clips at the collar and an adjustable belt holds the air hose out of the way of work. NIOSH approved.