Features: High quality rubber casters for office chairsHeavy duty and safe, fits all office chair bases with mounting holesTwin wheel design improves weight distribution and smooth operation, ease to glide and swivelSwivel and roll freely and more quietly in every direction with no need for maintenanceSoft rolling rubber wheel surface guaranteed to leave no mark on carpets or any kind of natural and engineered wood floor, tile floor, specialty floor, and smooth concrete/asphalt floorEasy to fit - Just click inSpecifications:Material: Steel and RubberWheel Diameter: 73mm (2-7/8 \") - Approx 3 \"Stem Length: Approx 22mm (7/8 inch)Stem Diameter: 10mm and 11mm (Look at the picture)Color: Black with transparentPackage includes: 1 x Chair Caster Our products are made with the highest quality materials and are designed to provide you with the best possible user experience.