Heavy weight capability and Durability made the wheel casters like the VXB005125BTPRF a must use, get your do it yourself object move around. The wheel diameter is 125mm or 4.921" inch in inches. Dimensions of the caster wheel is 50mm (1.969" inch). The Caster with the wheel from end to end is 166mm = 6.535" inch. Top Plate is the method of installing the caster to your equipment, here are the dimensions 100mm x 115mm with 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 507 lb and is Fixed type. Temperature range is -40 to 180 F. Buy our VXB005125BTPRF, we wish all the best.