Used to convert a swivel office chair with casters into a fixed chair without losing the chair height Standard stem size B diameter x height: 7/16 in x 7/8 in (11 mm x 22 mm), same dimension as most casters 2 inch glide height - similar to most chair casters. Not suitable for chairs using a 10mm stem caster Bottom Width 2 inches x Top Width 1.33 inches Ideal for converting your rolling stool or office chair to a more stable gliding style, or replacing your old, worn glides. Transform a rolling chair or rolling stool into a fixed chair with glides without affecting the overall height of the chair too much. Color: Black Material: Metal + Nylon Diameter: 50mm Package Contents: 25 * pcs Universal Casters Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in a little different from the real thing. The measurement allowed error is +/- 1-3 cm.