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