Altessa Grid Fabric - 99% Polyester / 1% Carbon|Color coded double strap webbing - ankle strap with side release buckle and top strap|Combination 1" elastic and webbing at top closure with snap adjustment|Female snap at back of boot|Hypalon sole|Meets standards required for use in ISO 5 (Class 100) - ISO 8 (Class 100,000) cleanrooms and other controlled environments