Upgraded Office Chair - High Performance Casters - Office Chair Replacement Part - Improves Strength.All-metal rolling bar with high height provides years of rolling lightweight 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 PU material, pressure resistant, quiet and smooth, will not scratch the floor, leaves no marks on the surface. Each wheel uses four ball bearings that are fashionable, comfortable, stable and quiet.Easy installation without tools or hardware. Simply remove the old R and slide it into position. Spindle size is 11mm diameter x 22mm (7/8;) is compatible, connt for 99% of office chairs (without IKEA).The wheels give your chairs a look more fashionable and more comfortable, making you satisfied with office chairs or ordinary chairs. Wheels will be the best choice to upgrade your chairs. Features: Universal Office Chair Base with Mounting Holes - Dual Wheel Design Improves Weight Distribution and Smooth Operation - Makes Sliding and Swiveling Easy - 4 Bearings - Maximum Load: 250 kg - Soft rubber surface leaves no marks or marks on natural and wooden floors, tiled floors, special floors and smooth concrete/asphalt floors - 2-step assembly process. Just grab your old ones and slide in your new ones, and you're ready to go. Technical characteristics : Material: steel and TPR rubber. Wheel diameter: 50 mm - Width: 20 mm - Height; installation: 57mm - Universal Fit: Rod Size: 11mm x 22mm (not compatible with Ikea 10mm x 22mm chairs) - Colour: Black - Contents: 5 swivel casters for office chair.