{HEAD ~ the waist} is centered at {TAIL ~ an axial distance} from the front end of the tip; and 
is centered at
{ HEAD ~ the waist } is centered at { TAIL ~ an axial distance } from the front end of the tip ; and
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH