filter regulator means for filtering the air entering the signal air path and for regulating the pressure in {HEAD ~ the signal air path} to {TAIL ~ a predetermined pressure} 
to
filter regulator means for filtering the air entering the signal air path and for regulating the pressure in { HEAD ~ the signal air path } to { TAIL ~ a predetermined pressure }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL