{HEAD ~ The apparatus} 1 wherein {TAIL ~ the three way valve} is located downstream of the pump means 
{ HEAD ~ The apparatus } 1 wherein { TAIL ~ the three way valve } is located downstream of the pump means
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH