{HEAD ~ a filter pack} disposed in the combustion chamber along {TAIL ~ an inner diameter} of the outer wall 
disposed along
{ HEAD ~ a filter pack } disposed in the combustion chamber along { TAIL ~ an inner diameter } of the outer wall
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH