A slidable tubular insert is carried within the principal conduit member and moves from {HEAD ~ an opened and closed position} to open or close {TAIL ~ an opening} in the principal conduit member and permit a formed article to move within 
to close
A slidable tubular insert is carried within the principal conduit member and moves from { HEAD ~ an opened and closed position } to open or close { TAIL ~ an opening } in the principal conduit member and permit a formed article to move within
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH