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