{HEAD ~ The biasing member} applies force to the stopper for pulling in the stopper into {TAIL ~ the receiving portion} 
{ HEAD ~ The biasing member } applies force to the stopper for pulling in the stopper into { TAIL ~ the receiving portion }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL