8" x 2-1/2" Polyon Cast Iron Wheel8" x 2 1 2" Polyon Cast Wheel Polyurethane elastomer tread chemically bonded to a cast iron core. These wheels are somewhat heavy and are ideal for warehouses with concrete and hardwood flooring. Tread: Polyurethane Elastomer Core: Cast Iron Core Bearing: Roller Bearing and Plain Bore Color: Red and Silver Durometer: Shore A 95 (+ 5) Temperature Range: 40 F to 180 F Wheel Diameter 8" Tread Width 2 1 2" Tread Type Polyurethane Elastomer Core Type Cast