A retainer 1 wherein {TAIL ~ said entering nose portion} has {HEAD ~ a rounded exterior surface} and an inner enlargement 
A retainer 1 wherein { TAIL ~ said entering nose portion } has { HEAD ~ a rounded exterior surface } and an inner enlargement
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH