{TAIL ~ The channel member} has a base wall and first and second opposed side walls having {HEAD ~ free, elongate edge regions} 
{ TAIL ~ The channel member } has a base wall and first and second opposed side walls having { HEAD ~ free , elongate edge regions }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD