The pot like housing is closed by {HEAD ~ a cover} 4 which has {TAIL ~ an inlet port} 5 for compressed air from a compressed air appliance 
has
The pot like housing is closed by { HEAD ~ a cover } 4 which has { TAIL ~ an inlet port } 5 for compressed air from a compressed air appliance
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH