Big and Tall Gas Cylinder for Your Office Chair Big and Tall replacement gas cylinder for your office chair This taller office chair shock adds an additional 2 to 6" in height Chair lift for taller people who need to sit higher in their office chair Will work as a taller gas pneumatic for Herman Miller Aeron chairs made before 2012. Not meant for stool height and is not an OEM Herman Miller gas lift This universal big and tall office chair hydraulic fits most any office chair