The SwitchTM lens system is an incredibly simple patented 1/4 turn SwitchTM buckle which makes the hassle of changing lenses a thing of the past. Simply turn the locking tabs to unlock your lens frame. Pop out your old lens and drop in a new one. * The anatomically correct AxisTM mask system offers the best in comfort for all facial contours.. The AxisTM is tested at twice the current impact ASTM and CE standards. Dye"s proprietary dual stage foam combines open and closed cell foam technology. Dual stage foam is specifically designed to "sheet" sweat and moisture away from your face, providing an undeniably resilient boundary between your eyes and perspiration. * Using patented technology the AxisTM precise blade angling and proven venting configuration, heat and moisture dissipates quickly. Scream Multi-Directional Venting makes communication with teammates effortlessly by carrying your voice farther.