24" Replacement Office Task Chair or Stool Base - Polished Aluminum - S4154 24" wide aluminum chair or stool base for new or replacement use Standard 2" (50mm) hub to receive standard chair gas lift cylinders Caster sockets measure 7/16" x 7/8" (11mm x 22mm) to receive standard casters mounting stems 2.5" (65mm) overall height of base without casters installed Polished aluminum with black painted underside