A plate has {HEAD ~ an opening} formed between {TAIL ~ two legs} for receiving the block and has two pins engaged into the extensions for rotating the plate relative to the base between a vertical position and a folded position 
formed between
A plate has { HEAD ~ an opening } formed between { TAIL ~ two legs } for receiving the block and has two pins engaged into the extensions for rotating the plate relative to the base between a vertical position and a folded position
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL 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