an outer cylinder depending from {TAIL ~ the insulation cap} and at least partially surrounding {HEAD ~ the inner cylinder} to define an annular exhaust gap for exhaust gas from the exhaust plenum 
an outer cylinder depending from { TAIL ~ the insulation cap } and at least partially surrounding { HEAD ~ the inner cylinder } to define an annular exhaust gap for exhaust gas from the exhaust plenum
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH