Steelcase Office Chair Stationary Castors - 5 SetStandard 7 16" x 7 8" (11mm x 22mm) grip ring mounting stem to attach to most standard chair or stool bases. Each caster wheels features a grip ring stem, which enables them to be attached to the base of an office chair without the use of any tools. 2 inches overall glide height when installedit similar height to most small chair casters. This Stool or office chair bell glides to convert any office or desk chair in stationary. This stool office chair