A small cannister 72 is mounted at the back edge of louver 62, and {HEAD ~ a large cannister} 74 is mounted at {TAIL ~ the front edge} 
A small cannister 72 is mounted at the back edge of louver 62 , and { HEAD ~ a large cannister } 74 is mounted at { TAIL ~ the front edge }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL