12" x 2-1/2" Energy Saver Polyon Cast Wheel - 2700 lbs. capacity12" x 2 1 2" Energy Saver Polyon Cast Wheel Crowned polyurethane elastomer tread chemically bonded to a solid heavy duty cast iron core. A combination of crowned tread and heavy core, offers higher weight capacities, durability, and greater mobility than standard Polyon wheels. Tread: Polyurethane Elastomer Tread Chemically Bonded To Cast Iron Core Core: Heavy Duty Cast Iron Core Bearing: Roller bearing Capacity: 2,700 Lbs. Color: Blue and Black