The housing 12 has a cup shaped design with {HEAD ~ a ventilation opening} 14 arranged at {TAIL ~ one end} and a valve seat 15 arranged at the other end 
The housing 12 has a cup shaped design with { HEAD ~ a ventilation opening } 14 arranged at { TAIL ~ one end } and a valve seat 15 arranged at the other end
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH