chairpartsonline Replacement Gas Lift Cylinder Pneumatic Shock - Fits Herman Miller Equa II Chair - Non-OEM S3490 Premium quality replacement gas lift cylinder made to fit only the Herman Miller Equa II chair - Non-OEM *** Does not fit other chairs Piston stroke / travel height adjustment range of 5" (up & down) Width of piston is 22mm (0.87") Overall length from end to end when fully extended is 15.6" & 10.6" when fully compressed Attachment hardware included: washers, bearing kit, & retaining clip