[Universal Size]: These stool or office chair glides have a standard 7/16 inch x 7/8 inch (11mm x 22mm) grip ring stem to attach to standard chair 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 as a set of 5 supports 250lbs. [Multi-functional Glides]: Durable solid NYLON structural glide design to handle more weight on desks, shop chairs, cabinets. The fixed glide casters are a great choice for office and home furnishings. [Quick Installation]: Our replacement glides have a new stem design, no tools needed, just pull out your old casters and insert these. Colour: 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 measurement allowed error is +/- 1-3cm.