BAFFIN Icebear Polyurethane The first PU boot of its kind, manufactured specifically for the North American climate. The PU compound is engineered to insulate the foot from the outer climate without the need of an inner liner. Its lightweight PU midsoles provide improved comfort and reduced fatigue. Acid and oil resistant rubber outsoles bring improved flexibility and traction. Wide fit through the calf and foot; thermal PU compound is cold crack resistant to -50° C.