Listing is for 1 (one) CasterHQ swivel caster fitted with our 4 inch diameter by 2 inch wide Semi Steel cast iron wheel and top lock brake. Wheel rotates on roller bearing. 1,000 pound capacity per caster. Top plate size 4" x 4-1/2"; Bolt hole dimensions: 2-5/8" x 3-5/8" to 3" x 3"; Load height: 5-5/8". Quality casters featuring double ball bearing heat-treated raceways, bright zinc plating, grease fittings and 5/8"(.625 inch) bolted kingpins (swivel models). These casters are great for dollies, plat-form trucks, warehouse carts and freight terminals. Our heavy duty high quality medium heavy duty casters are well-suited for most all industrial and commercial equipment. Also recommended and installed on drywall carts, welding carts, and wall panel carts and much more!