Special Order Item Harper Trucks MPN: WH51S Harper Trucks WH-51S Truck Caster Molded On Rubber 6 Inch Diameter Harper Trucks WH-51S replacement truck caster with molded-on rubber tread and 6 Inch diameter wheel. Replacement wheel for hand trucks and cylinder trucks across warehouse operations, fleet... $92.42 / EA Decrease Quantity of undefined Quantity Increase Quantity of undefined