Heavy weight capability and Durability made the wheel casters like the VXB007B063PVC a must use, get your do it yourself object move around from our Toronto biz. Dia. Measured of the caster wheel in metric standard 63mm which is equal to 2.480" inch with imperial units. Sizes of the caster wheel is 30mm (1.181" inch). The caster dimensions heightwise is 90mm/3.543" inch. Top Plate is the method of installing the caster to your equipment, dimensions are 92mm x 65mm with the holes distance of 73mm x 45mm. Low drag was achieved by a Polyvinyl Chloride core on a Polyvinyl Chloride tire spinning freely with a Ball bearing. Each caster wheel will carry the load of 66 lb and is Swivel type. Ambient temperature range is -40 to 180 F. FYI, you will need to buy the VXB007B063PVC in order to get one :).