Zenith X Air, A size adjustment system which integrates three components for all-day comfort. A new, double diameter dial allows for easier size adjustments. Ergonomic side wings ensure a fast and secure fit against the back of the head. The patented Self Adaptive Live Hinge is the latest, self-adjusting fit technology that moves as the wearer moves. Chinstrap designed with eco-leather, a synthetic leather made using sustainable materials and processes, that provides high degrees of comfort and significantly reduces irritation to the skin. Hypoallergenic and washable. Integrated slots that enable seamless accessory attachment. Applies to KASK eye, face, and hearing protection. Advanced composite fabric integrated with Hydrocool® moisture-wicking technology and exceptionally soft textiles for enhanced user comfort. Infused with a deodorizing silver ion treatment.