{TAIL ~ A hydraulic or pneumatic actuator} wherein the movement of the power transfer shaft is controlled by {HEAD ~ a movable vent} 
{ TAIL ~ A hydraulic or pneumatic actuator } wherein the movement of the power transfer shaft is controlled by { HEAD ~ a movable vent }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD