Tens of thousands of different kinds to select from to have your office Desk/chair sliding easily right and left, install the VXB009C125BFS. The wheel diameter is 125mm or 4.921" inch in inches. The thickness of the wheel is 75mm or 2.953" inch. The Caster with the wheel from end to end is 185mm = 7.283" inch. Top Plate is the method of installing the caster to your equipment, here are the dimensions 200mm x 153mm Top Plate: 14mm+housing: 10mm with the holes distance of 160mm x 90mm. Low drag was achieved by a Cast iron polyurethane core on a Cast iron polyurethane tire spinning freely with a Precision double ball bearing. Bearing in mind that every caster wheel has the load capacity of 2205 lb with a Swivel type. Temperature range is -40 to 180 F. Very important notice, you need to buy the VXB009C125BFS in order to get one :).