SCAFFOLDING AND PARTS THEREOF-NAMELY, STANDARDS (UPRIGHT POSTS), PUNCHEON UNITS AND PROPS, FORK HEADS, GUARD RAIL SUPPORTS, TRANSOMS AND BOARD BEARERS, BRACES, LEDGERS, AND LEDGER BEAMS, COLLARS, BASE PLATES, TIE BARS, BATTENS AND SCAFFOLD BOARDS, BOARD CLIPS, BRACKETS AND EXTENSION BRACKETS, AND COUPLINGS