Women's Bogs Footwear Classic II Adjustable Calf Winter Boots Durable, hand-lasted rubber with a four-way stretch inner bootie. 90° heel for support on rough uneven terrain. Nylon shank in midsole for support and stability. Constructed with 7mm Neo-Tech waterproof insulation. BOGS Max-Wick evaporates sweat to keep feet dry. Self-cleaning outsole. BLOOM eco-friendly, algae-based EVA footbed that helps clean polluted water habitats. 100% Waterproof. Comfort rated to -40°F/-40°C.