The insert member fits within {HEAD ~ a sleeve member} which is formed of {TAIL ~ a semiresilient material} capable of maintaining its shape at rest but capable of being flexed when subjected to a force 
The insert member fits within { HEAD ~ a sleeve member } which is formed of { TAIL ~ a semiresilient material } capable of maintaining its shape at rest but capable of being flexed when subjected to a force
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH