Fangrui Product Details Casters You Can Keep - Our Premium Caster Wheel Stem Diameter Is 7/16 Inch(11mm),stem Length Is 7/8 Inch(22mm), Duty Design Supports Up To 500 Lbs As A Set Of 5 Smooth Quiet Rolling - Wheel Materials Are Made Of High-quality Polyurethanes, Which Are High Mechanical Strength, Wear Resistance, Shock Absorption And Low-noise. These Features Help Roll Easily And Cause No Squeaky Sounds Or Noise Of Any Kind. Safe For Floors - Smoothly And Quietly Roll Around On Any Hardwood, Ceramic Tile, Wood, Carpet, Especially Cement Floors Without Scratching, Please Pay Attention To Safety Due To Less Resistance Force Easy To Install - Simply Pull Your Old Casters Out, Then Plug The New Wheels In, Universally Fit For Standard Seats: Work Stools, Office Chairs, Dining Chairs, Desk Wheels, Tool Carts Etc Colour:black Material:pu Size:50mm Package Contents: 5 X Caster Wheels Only The Above Package Content, Other Products Are Not Included. Note: Light And Different Displays May Cause The Color Of The Item In T