The shaft is connected to {TAIL ~ a movable vent follower} located at the interface between {HEAD ~ the cells} 
The shaft is connected to { TAIL ~ a movable vent follower } located at the interface between { HEAD ~ the cells }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD