NBR blended NR rubber boots with polyester lining|NBR rubber for maximum chemical protection|Handcrafted 100% waterproof-, and oil-resistant|Fire retardant upper provides flame and thermal protection|30% concentration Sodium Cyanide resistant >480 minutes|Self-cleaning NBR lug sole|Reinforced heel and instep|Cement-. fuel-, and oil-resistant sole|Sole resistant to 300°C/572°F hot contact|Super slip-resistant|Ergonomic orthotic insoles included|Hang up holes on the sides of each boot|Snug fit design to provide extra comfort and safety and reduce incidences of ankle roll-over|12" tall boot|Ultra flexible: Exceeds 305,000 Flex Rating|Compatible with ice studs