{TAIL ~ A piston} is disposed in each cylinder for reciprocal movement therein in order to pump the fluuid from {HEAD ~ the inlet} to the outlet 
{ TAIL ~ A piston } is disposed in each cylinder for reciprocal movement therein in order to pump the fluuid from { HEAD ~ the inlet } to the outlet
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH