A plunger mounted in the casing for free vertical movement within a selected range has a disc like {HEAD ~ foot} positioned for free engagement by {TAIL ~ the diaphragm} 
A plunger mounted in the casing for free vertical movement within a selected range has a disc like { HEAD ~ foot } positioned for free engagement by { TAIL ~ the diaphragm }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL