[Universal Size]: These stool or office chair glides have a standard 7/16 inch x 7/8 inch (11mm x 22mm) mounting ring to attach to standard chairs or stool bases, please measure yours before ordering. [Fixed and Strong]: The stationary casters can be used on wood, metal and tubular metal chairs, furniture and other equipment, per glide foot as a set of 5 supports 250 kg. [Multifunctional Glides]: Durable solid NYLON structural glide design to handle more weight on desks, workshop chairs, cabinets. The fixed glide casters are a good choice for office and home decor. [Quick Installation]: Our replacement glides have a new spindle design, no tools needed, just pull out your old wheels and insert these. Color: black Material: Metal + plastic Package contents: 5 * glides Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The allowed measurement error is +/- 1-3 cm.