A bi directional flow control valve includes {HEAD ~ a two port housing}, and a hollow cage within {TAIL ~ the housing} 
A bi directional flow control valve includes { HEAD ~ a two port housing } , and a hollow cage within { TAIL ~ the housing }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL