a base mounted on {HEAD ~ a bottom} of {TAIL ~ said housing} and provided with a plurality of tubular portions thereon 
of
a base mounted on { HEAD ~ a bottom } of { TAIL ~ said housing } and provided with a plurality of tubular portions thereon
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH