By having annular lower portion 38 resiliently hinged, a spring action is realized as {HEAD ~ annular lower portion} 38 passes over {TAIL ~ annular container flange} 18 
By having annular lower portion 38 resiliently hinged , a spring action is realized as { HEAD ~ annular lower portion } 38 passes over { TAIL ~ annular container flange } 18
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH