said core formed of {HEAD ~ polypropylene} and {TAIL ~ said coating} formed of polyethylene, 
said core formed of { HEAD ~ polypropylene } and { TAIL ~ said coating } formed of polyethylene ,
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH