The steel toe Mt Vernon 6" Mid Work Boot is a high-performance boot for medium to heavy duty. This waterproof boot is made with KEEN.DRY technology that lets vapor out without letting water in. Hydrophobic/hydrophilic 2-zone comfort lining. Direct attach PU midsole. Integrated PU heel cushion. Removable metatomical dual density EVA footbed. KEEN.Grip oil and slip resistant non-marking rubber outsole meets or exceeds ASTM F1677-96 Mark II non-slip testing standards. Electrical hazard protection meets or exceeds ASTM F2412-11 and F2413-11 I/75 C/75 EH standards. Not compatible with aftermarket insoles or orthotics.