The Bogs Crandall II Zip boot is an 100% waterproof boot to keep you warm and dry this winter. Inside is a BLOOM eco-friendly, algae-based EVA footbed that is not only comfortable but helps clean polluted water habitats. This boot is constructed with 3MM Neo-Tech waterproof insulation along with a BOGS Max-Wick evaporates sweat to keep feet dry. Underfoot is their Rebound cushioning which provides all-day comfort and energy return. Another great feature is the steel shank built into the outsole for stability and support. This boot has a zipper on lateral side for easy entry plus a low pile faux fur lining for warmth and comfort. Comfort rated to -40°F/-40°C.