The flanges direct {HEAD ~ convection} of hot gases along {TAIL ~ the housing inside surface} to vaporize grease 
The flanges direct { HEAD ~ convection } of hot gases along { TAIL ~ the housing inside surface } to vaporize grease
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH