Designed for extreme conditions, this boot has everything you need to battle the elements. Externally, the MS-2 molded outsole offers reliable traction on snow, mud and icy ground, and the stretch-fit topline snugs right up against your calf to keep snow, freezing wind and rain out, and all the warmth in. Inside, a soft fleece lining is just the beginning there's also a cushioning EVA midsole and a 2mm thermal foam layer under the footbed for complete supportive comfort. 100% Waterproof. Comfort Range: -40° to 40°F.