Another advantage of the invention is that the glass core can be substantially centered with {HEAD ~ respect} to {TAIL ~ the larger diameter exterior surface} of the second sleeve 
to
Another advantage of the invention is that the glass core can be substantially centered with { HEAD ~ respect } to { TAIL ~ the larger diameter exterior surface } of the second sleeve
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH