A broad space is formed between the rib and a back plate portion of the groove so as to interrupt the flow of {HEAD ~ rain water} running toward {TAIL ~ the interior} of building frame 
running toward
A broad space is formed between the rib and a back plate portion of the groove so as to interrupt the flow of { HEAD ~ rain water } running toward { TAIL ~ the interior } of building frame
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 REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH