Tens of thousands of different kinds to select from to have your office Desk/chair sliding easily right and left, install the VXB20050BPP2L. And rolling on wheel that has 50mm diameter/1.969" inch. Dimensions of the caster wheel is 50mm (1.969" inch). Overall height of the wheel caster is 48mm = 1.890" inch. is the method of installing the caster to your equipment, here are the dimensions 38mm x 38mm with the holes distance of 129mm x 74mm. The weehl core material is Polypropylene and has a Polypropylene tire with a low friction Roller bearing. Each caster will carry the load of 77 lb and is Swivel type. Temperature range is -40 to 180 F. Very important notice, you need to buy the VXB20050BPP2L in order to get one :).