The shaping means is then moved proximally along a first predetermined contour, to a proximal area on the tube, and then along a second predetermined contour, symmetrical to the first predetermined contour, back to {HEAD ~ the point} of {TAIL ~ entry} 
of
The shaping means is then moved proximally along a first predetermined contour , to a proximal area on the tube , and then along a second predetermined contour , symmetrical to the first predetermined contour , back to { HEAD ~ the point } of { TAIL ~ entry }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 REL TAIL TAIL TAIL TAIL TAIL