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