CARBON-FIBER TOE: Left and right asymmetrical, non-metallic carbon-fiber (composite) toes offer unobtrusive fit and are 15% lighter than steel; These boots meet or exceed ASTM F3445 and F2413 M I/75, C/75 EH standards WATERPROOF: KEEN.DRY is a waterproof, breathable membrane liner, keeping your feet dry and comfortable; Full-grain barnyard resistant waterproof leather helps resist the damaging effects of oleic acid, urea, sodium chloride, and ammonium hydroxide TRACTION: Oil- and slip-resistant, non-marking, rubber outsoles that meet or exceed ASTM F1677 MARK II non-slip, and ASTM SATRA TM31 material abrasion testing standards; Featuring KEEN.ToughSole a non-rubber outsole that is lighter and tougher than rubber PROTECTION: Made with a nylon shank, used for midfoot support, and torsion stability; Meets ASTM D471 #903 standards for oil and isooctane chemical resistance; Featuring a Made with a 360° Goodyear welt construction for enhanced durability and flexibility INSULATION & COMFORT: These boots come with KEEN Luftcell, air-infused midsoles for weightless comfort; Featuring 600G of KEEN.WARM insulation rated at -55°F/-48°C, and a moisture-wicking lining to help keep feet warm and dry