Heavy weight capability and Durability made the wheel casters like the VXB005200CB1 a must use, get your do it yourself object move around from our Toronto biz. Wheel dia. is 200mm or 7.874" inch in inches. The wheel has a width of 50mm=1.969" inch. The Caster with the wheel from end to end is 240mm = 9.449" inch. Mounted via a Top Plate that has a size of 100mm x 115mm and the holes distance of 75mm x 85mm. Low drag was achieved by a Cast iron core on a Cast iron tire spinning freely with a Roller bearing. Each caster wheel will carry the load of 661 lb and is Swivel and Center Brake type. The Temperature range is -40 to 180 F. FYI, you will need to buy the VXB005200CB1 in order to get one :).