The valve stem is restricted from moving further away from {TAIL ~ the valve body} by {HEAD ~ the annular protrusion} 
The valve stem is restricted from moving further away from { TAIL ~ the valve body } by { HEAD ~ the annular protrusion }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD