The interior of housing 2 on {HEAD ~ the spring 24 side} of diaphragm 7 is vented to the atmosphere by a bore 30 formed through {TAIL ~ pin} 26 
The interior of housing 2 on { HEAD ~ the spring 24 side } of diaphragm 7 is vented to the atmosphere by a bore 30 formed through { TAIL ~ pin } 26
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH