Minimization of possible untoward effects on operator by installing VXB005100BLTPRF just ask your operator to push and pull, but not carry. The wheel diameter is 100mm or 3.937" inch in inches. Dimensions of the caster wheel is 50mm (1.969" inch). The caster dimensions heightwise is 142mm/5.591" inch. Mounted via a Top Plate that has the size of 100mm x 115mm and the holes distance of 75mm x 85mm. Low drag was achieved by a Thermoplastic Rubber core on a Thermoplastic Rubber tire spinning freely with a Double ball beaing. Each caster will carry the load of 441 lb and is Fixed type. Temperature range is -40 to 180 F. Very important notice, you need to buy the VXB005100BLTPRF in order to get one :).