{TAIL ~ Each channel section} may include a flange along at least one side thereof, the connection mechanism being provided on {HEAD ~ the flange} 
{ TAIL ~ Each channel section } may include a flange along at least one side thereof , the connection mechanism being provided on { HEAD ~ the flange }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD