The locking device includes {HEAD ~ a retainer} which carries {TAIL ~ a radially movable locking members} that are cammed outward by downward movement of the tieback member relative to the retainer 
carries
The locking device includes { HEAD ~ a retainer } which carries { TAIL ~ a radially movable locking members } that are cammed outward by downward movement of the tieback member relative to the retainer
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH