a case substantially equal in {HEAD ~ size} to {TAIL ~ a conventional glow starter case}; and 
to
a case substantially equal in { HEAD ~ size } to { TAIL ~ a conventional glow starter case } ; and
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH