{TAIL ~ Vertical movement} of the plunger actuates a cam or screw to vary {HEAD ~ the setting} of the control element of the level control system 
{ TAIL ~ Vertical movement } of the plunger actuates a cam or screw to vary { HEAD ~ the setting } of the control element of the level control system
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH