Special Castor Wheels for computer chair and swivel chair   Materials: PU   Durable and no harm to the floor   Simple to install without tools, plug and play   Suitable for swivel chairs, computer chair, office chair, furniture, computer desk and baby bed, etc   5 Castor Wheels per group   Suitable for all hard surfaces, such as parquet flooring, ceramic tile, stone, concrete, marble, carpet, etc.   Easy fit clip system   Roller point Wheel color: black Wheel diameter: 50mm