You need 8inch-Swivel-Caster-021 to have your office desk, equipment or even a machine to easily roll them around. Diameter of the caster wheel is a metric standard 200mm that is equal to 7.874" inch with imperial units. The wheel has a width of 50mm=1.969" inch. The Caster with the wheel from end to end is 268mm = 10.551" inch. Mounted via a Top Plate that has the size of 138mm x 110mm x 10mm and the holes distance of 110mm x 75mm. Low drag was achieved by a Cast iron polyurethane core on a Cast iron polyurethane tire spinning freely with a Precision double ball bearing. Here come the maximum load that should be applied on every wheel, remember to add safety factor, when calculating the load capacity 1543 lb with a Swivel type. Temperature range = -40 to 180 F. Remember, you will have to buy the 8inch-Swivel-Caster-021 in order to have it :).