Determine the capacity of your truck or cart by choosing one of these caster sets. Both of these sets are moldon rubber wheels with cast iron hubs which are the highest capacity wheels available. Each caster set includes 2 Rigid and 2 Swivel wheels. Best suited for smooth indoor floors. 5 inch caster has a 1600 pound load capacity and the 6 inch caster has a 1800 pound capacity. Plate measures 4 3/8 inches front to back and 3 3/4 inches side to side. Bold holes are 3 1/8 inches front to back and 2 5/8 inches side to side.Choose a caster set and place your order to bring greater efficiency to your workplace