zitriom Premium Office Chair Caster Wheel Universal Standard Size 11mm Stem Diameter X 22mm Stem Length (7/16" X 7/8") RELIABLE - These Premium Casters are especially designed to Protect Hardwood, Carpet, Slate, Tile, and other type of Floors HEAVY DUTY and DURABLE - Office Chair Caster Wheels Maximum Weight Rating: 100 lbs EACH wheel and 500 lbs as a set of 5 PRACTICAL AND MULTI-PURPOSE - Work Perfect On Hardwood floors, Carpets and any Tile, or slate. Made of Polyurethane Material UNIVERSAL - These Rollers Fit Most Office Chair Models Available - Standard Stem diameter: 7/16"(11mm), stem length: 7/8"(22mm) USER FRIENDLY - DIY Easy pull and snap installation - 5-year Warranty - Free No-hassle Replacement or Money Back Guarantee