PREMIUM QUALITY CASTERS: The office chair casters are made of high quality impact resistant plastic. After 5 days of use, the wheels will no longer loosen or break like other brands. With the casters, you get what you pay for! ONE SIZE FITS MOST: The casters are 50 mm in diameter and fit almost all office chair models, as this is the most common diameter in corporate office chairs. Adapts to your movement: The casters can rotate 360° to adapt to your movement. They can be used anywhere, even on hard floors. Therefore, you will not have the problem of the casters getting dirty or wearing out quickly, as you can find with conventional casters from other brands. Will not damage floors: When using traditional casters, you often leave scratches or black marks on the floor. The casters are not affected and will not damage the floor. However, it is recommended to put a mat under the chair to make it easier to move. Note: The data are all measured manually, please allow an error of 1-3 cm due