staff chair: electroplate frame(MOQ:50PCS) .Polyester cover,Premium PP shell,50kg/CBM one time shaped PU foam.12cm seat.PP armrest and dust-proof cover. Armrest support made by 22*T2.0 round tube. Feet made by moulded triangle tube.Aluminum alloy made armrest and base. Base have liftunction. Nylon castor(castor size:∮50MM, PA Nylon castor has no broken under 50000times resistance and fatigue test).Andco 80*80 gas lift bar,it can stretch out and draw back 120000times without leak.