As a result {TAIL ~ the tips} of the extending rings are blunted to create metal to {HEAD ~ metal} seals on the surrounding tubular 
As a result { TAIL ~ the tips } of the extending rings are blunted to create metal to { HEAD ~ metal } seals on the surrounding tubular
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH