The suction channel being configured to receive {HEAD ~ a valve member} that controls {TAIL ~ flow} through the suction channel 
The suction channel being configured to receive { HEAD ~ a valve member } that controls { TAIL ~ flow } through the suction channel
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH