A reinforcing agent is placed between {HEAD ~ each} of {TAIL ~ the barbs} of the connector  
of
A reinforcing agent is placed between { HEAD ~ each } of { TAIL ~ the barbs } of the connector
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH