AMERICAN BUILT with materials from around the world. Integrated PU heel cushion. KEEN.Dry waterproof breathable membrane. Left and right asymmetrical steel toe. Meets or exceeds ASTM F1677-96 Mark II non-slip testing standards. Meets or exceeds ASTM F2412-11 and F2413-11 I/75 C/75 EH standards. Not compatible with aftermarket insoles or orthotics. TPU stability shank.