The shoulder region merges into and provides {TAIL ~ a transition} between {HEAD ~ the finish} and a sidewall portion 
The shoulder region merges into and provides { TAIL ~ a transition } between { HEAD ~ the finish } and a sidewall portion
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH