The invention 7, wherein the first detent means comprises an annular array of detent teeth, a first segment of the array comprising {HEAD ~ a first number} of {TAIL ~ detent positions} and a second segment of the array comprising a second number of detent positions; and 
of
The invention 7 , wherein the first detent means comprises an annular array of detent teeth , a first segment of the array comprising { HEAD ~ a first number } of { TAIL ~ detent positions } and a second segment of the array comprising a second number of detent positions ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH