Herman Miller used different vendors for their gas cylinders.
The trigger for the gas cylinder came in different lengths depending on source, so they designed
what's called a setscrew that sits on top of the trigger and pushes down on it
to activate it. Since the trigger was in different lengths the setscrew can be
adjusted so that it's not engaging the trigger all the time which happening with some chairs. There is a video on YouTube how to adjust the setscrew. You can
do a search for: aeron chair setscrew and you will see the video.