Executive chair:leatherette armrest support made by∮40*20*2.0 tube, 45kg/CBM foam, 12cm seat and back board,homemade duble function base, have lift, tilt and lock function, polished aluminum alloy feet, PU big caster(caster size:∮60MM,castor has no broken under 50000times resistance and fatigue test).Andco 80-40# gas lift bar,it can stretch out and draw back 120000times without leak.