Features: Smooth and Quiet Ride - The 2 inch Rollerblade style wheels work great on hardwood, tile and even carpet. All parts are made from high quality and provide the smoothest maneuverability. Ball diameter is 2 inches 50mm antique gold balls casters, stem length is about 1.5 inches (38mm) with stems and sockets Easy Installation - Our wheels will fit most standard office chairs that are made in North America (US and Canada). Please measure your old caster first. To Installation - Just pop off your old wheels (you may grip them with a glove or towel) and push on your new Rollerblade style wheels. Bonus Round - Gives your old chairs new life. Gives your new chairs upgraded performance Whisper quiet operation. PU wheels will NEVER scratch wood floors Upgrade your office wheel chairs with our 2.5" Rollerblade style wheels for your office chair. Specifications: Material: Polypropylene/PP and Steel Wheel Size: 50mm/ 2-inch.. Stem size: 8 x 38mm/ 0.314 x 1.50inch (L x W). Wheel Thickness: 2.4cm/0.94" Capacity: 66lbs(30kg) Colors: Antique Gold Special feature: Swivel Quantity: 5 Pc Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! No Retail Package Package Includes: 5 x Rolling Caster