{HEAD ~ The packaging} comprises {TAIL ~ two generally hollow half shells} connected to each other in face to face relationship along their associated mouth edges 
{ HEAD ~ The packaging } comprises { TAIL ~ two generally hollow half shells } connected to each other in face to face relationship along their associated mouth edges
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH