At least portions of {HEAD ~ the interior surface} of {TAIL ~ the side wall} and base define a cavity within the housing 
of
At least portions of { HEAD ~ the interior surface } of { TAIL ~ the side wall } and base define a cavity within the housing
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH