The Zzero 4 ski boot offers optimal downhill performance as well as maximum freedom of movement when ascending, while the combination of boot and liner means first-class comfort. The material mix of Pebax® on the cuff/shell/tongue, carbon on the Powerstringer, and magnesium on the buckles. Together explain why this boot is so versatile and why the ZZeros are currently the lightest 4-buckle boots on the market. Available with our new super-light thermoformable Thermoflex liner. Now available in a full size run of unisex shell sizes and custom formed liners.