This boot is designed for absolute warmth in the coldest environments, and features a removable three layer insulating liner to capture warm air and maintain warmth. It is rated to -40 degrees Celsius. This boot also features a composite thermatoe and a steel plate, and offers electrical hazard protection. It has a direct inject polyurethane shell midsole and a polyurethane outsole. The composite toe meets ASTM F2413-05 standards.