The material of the inner liner is folded over at opposite edges to form {TAIL ~ increased thickness margins} at {HEAD ~ opposite ends} of the pack 
The material of the inner liner is folded over at opposite edges to form { TAIL ~ increased thickness margins } at { HEAD ~ opposite ends } of the pack
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH