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