{HEAD ~ A water flow sensing unit} is secured between {TAIL ~ the inlet port} and the flow discharge port 
is secured between
{ HEAD ~ A water flow sensing unit } is secured between { TAIL ~ the inlet port } and the flow discharge port
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH