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