As described above, the cover 43 is provided over the entire circumferential end edge with a base attachment piece {TAIL ~ 432 U} shaped in {HEAD ~ cross section} 
As described above , the cover 43 is provided over the entire circumferential end edge with a base attachment piece { TAIL ~ 432 U } shaped in { HEAD ~ cross section }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD