A spring is supported on {TAIL ~ the counterholder} and is intended for prestressing {HEAD ~ a closing part} against a valve seat 
A spring is supported on { TAIL ~ the counterholder } and is intended for prestressing { HEAD ~ a closing part } against a valve seat
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH