Left and right asymmetrical steel toes. KEEN.KEY-TECH FLEX: contoured underfoot support provides structured stability and comfort. Contoured heel lock. Reflective webbing for additional safety and visibility. Meets ASTM F1677-96 MARK II non-slip testing standards. Meets ASTM F2913 SATRA non-slip testing standards. Meets ASTM F2412-11 and F2413-11 M I/75 C/75 EH standards. Cleansport NXT(TM) for natural odor control.