The angular position of {HEAD ~ the chuck} is adjusted and locked by {TAIL ~ the detent ring assembly} 
The angular position of { HEAD ~ the chuck } is adjusted and locked by { TAIL ~ the detent ring assembly }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL