Universal standard rod size: 11mm x 22mm, suitable for 96% of standard size office chairs on the market. (Please confirm your chair size before ordering to ensure this wheel is suitable). Wide range of applicable floorsQuiet and smooth, no damage to the floor, strong applicability. Wooden parquet floors, short woolen blankets, tiled floors, etc. When you roll to any corner of your office or home, you will feel safe. Easy to install: This type of wheel is very easy to install without tools. Simply remove the old wheel, then align the connecting rod of the new wheel with the socket on the chair and press down to complete the installation. Additional Benefits: Strong load-bearing capacity (the maximum load-bearing capacity of 5 wheels can reach 700 kg), new wear-resistant TPR rubber material, silent sliding does not damage the floor, dust-proof wheel cover (coating design dust-proof rubber on both sides of the wheel, effectively preventing dust and hair). Note: The data is manual measurement, please allow 1-26cm error, due to differences between light and screen, there will be a certain color difference, the specific received in kind prevail.