Upgraded Office Chair - High Performance Casters - Office Chair Replacement Part - Improves Strength. All-metal roll bar with high height provides years of rolling light and durable. The sturdy design (5-pack) can support 250 kg (weight). The wheel bar is strong and durable, and the design is more sturdy. Wide and thick double wheel structure, soft polyurethane material, pressure resistant, quiet and smooth, does not scratch the floor, does not leaves no marks on the surface. Each wheel uses four high quality ball bearings which are fashionable, comfortable, stable and quiet. Easy installation without tools or hardware. Just remove the old R and slide it into position. Spindle size is 11mm Dia x 22mm (7/8") L is compatible, connt for 99% office chairs (without IKEA). Wheels give your chairs a more fashionable and comfortable look, which makes you satisfied with office chairs or ordinary chairs.Wheels will be the best choice to upgrade your chairs.