The direction that {HEAD ~ the retainer} is moved into {TAIL ~ the temporarily secured position} is generally at right angles to the direction the retainer is moved from the temporarily secured position to the fully secured position 
is moved into
The direction that { HEAD ~ the retainer } is moved into { TAIL ~ the temporarily secured position } is generally at right angles to the direction the retainer is moved from the temporarily secured position to the fully secured position
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH