Preferably, the valve member is compressed within the chamber to provide {HEAD ~ the resilient bias} required to move the valve member into sealing engagement with {TAIL ~ the valve seat} 
Preferably , the valve member is compressed within the chamber to provide { HEAD ~ the resilient bias } required to move the valve member into sealing engagement with { TAIL ~ the valve seat }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL