The outsoles of the GB00102 10" Carbo-Tec Composite Toe Waterproof Work Boot starts with real rubber, which is one of the most durable, longest lasting materials in outsole construction. Next, a rare blend of proprietary materials is added to give Carbo-Tec soles chemical and oil resistance. This compound makes the boot highly oil and slip-resistant. The result is an extremely long wearing, non-marking outsole that is flexible and most importantly, comfortable. This composite toe boot is also equipped with a PVC midsole, Comfort Core footbed, high-performance mesh lining and heel-stabilizing counter lock. ASTM F2413 protective toe classification Georgia waterproof system Fiberglass shank Removable brush guard kiltie Goodyear welt construction.