The side edge portion of {TAIL ~ the front plate portion} 14 is internally bent to form a lip 14 a, the tip end of which is adapted to be contacted with the surface of a building board 30 to be fitted in {HEAD ~ the groove portion} 12 
The side edge portion of { TAIL ~ the front plate portion } 14 is internally bent to form a lip 14 a , the tip end of which is adapted to be contacted with the surface of a building board 30 to be fitted in { HEAD ~ the groove portion } 12
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH