Load-bearing and wear-resistant, waterproof and rust-proof, quiet and mute, saving trouble and effort Thickened steel plate is load-bearing and compressive, plastic wear-resistant is non-toxic and harmless Installation height: 61mm Wheel width: 25mm Wheel diameter: 38 mm Single weight: 40 kg Thickness square plate: 2mm Backing thickness: 2mm Easy to install: Simply remove the old casters from the chair. Then firmly insert the new casters and make sure they are securely held by the chair.; Universal Fit: Our office chair casters are designed according to standard. They adapt to almost all office chairs available on the market. Does not damage any floor: move around on your chair in the office or at home without worrying about scratching or scratching. damage your floor. Casters won't damage any floor including tile, carpet and parquet Colour: Black Size: 6.3*4.3*6.1 cm. Quantity delivered: 4 pieces Product dimensions are all measured by hand, there are errors and the actual product shall prevail. Product color is affected by shooting light view and there is a slight color difference, which depends on the actual product received.