{HEAD ~ The stopper} has a first end portion and a second end portion, the first end portion being fixed to {TAIL ~ the cover} 
{ HEAD ~ The stopper } has a first end portion and a second end portion , the first end portion being fixed to { TAIL ~ the cover }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL