The Premier Office Chair Caster Wheels 50mm (Black/Black) Set of 5. - Standard Size wheel will fit most chairs. QUALITY!!! MATERIALS & SERVICE: Made with high quality Polyurethane exterior in our Unique Production Process. Protect Your Hardwoods & Floors. Guaranteed for 5 years. As a small business we are able to deliver superior quality products & customer support than our competitors. You're in safe hands. ENVIRONMENTALLY FRIENDLY MATERIALS: Other casters usually made with cheap material (usually PVC, it's an not eco-friendly material, after short time of use the material will peel and come off. GUARANTEED TO LAST: Made with High Quality Steel. Each Wheel can hold up to 100lbs, (500lbs total with 5 wheels.) NO SCRATCHES: Save Money, No Need for Floor Mats at Home and Office. Designed to prevent scratches and Protect all Hardwood Floors, Laminate, Tile and Slate. These are caster wheels that you will take with you to your new office chair. STYLISH DESIGN: Sophisticated Black Office Wheels