The exterior surface of the ferrule comprises {HEAD ~ a circumferential ridge} and {TAIL ~ groove} that reversibly interacts with a spring inside the adapter cavity 
The exterior surface of the ferrule comprises { HEAD ~ a circumferential ridge } and { TAIL ~ groove } that reversibly interacts with a spring inside the adapter cavity
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH