A controller is preferably in communication with each of {HEAD ~ the valves} for selectively moving {TAIL ~ each} of the valves between an open position and a closed position 
for selectively moving
A controller is preferably in communication with each of { HEAD ~ the valves } for selectively moving { TAIL ~ each } of the valves between an open position and a closed position
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH