ELECTRICAL APPARATUS-NAMELY, CONDUIT FITTINGS, OUTLET BOXES, SWITCH BOXES, BOX CONNECTORS, CONDUIT COUPLINGS, FIXTURE EXTENSION PIECES, FIXTURE STEMS WHICH ARE TUBULAR STUDS FOR SUPPORTING SUSPENDED LIGHT FIXTURES, BUSHED ELBOWS, CONDUIT NIPPLES, CONDUIT END FITTINGS, CONDUIT BUSHINGS, CLAMPS FOR CONDUITS, REDUCERS AND REDUCING CONNECTORS, CABLE CLIPS, CABLE CLAMPS, STAPLES FOR CABLES, UNIONS FOR CONDUITS, METER CONNECTORS, CONDUIT ELBOWS, ENTRANCE FITTINGS, GROUNDING FITTINGS, LOCK NUTS, BUSHINGS FOR OUTLETS THROUGH WHICH CABLES PASS, WHETHER PLAIN OR OF THE CAPPED TYPE AND OF THE SNAP-IN TYPE AS WELL AS BLANK BUSHINGS, CONCRETE RINGS AND BOXES ESPECIALLY ADAPTED FOR USE IN CONCRETE CONSTRUCTION, SWIVEL, HANGER COVERS WHICH ARE HOUSINGS FOR SWIVELS THAT SUSPEND TUBULAR STEMS BY WHICH ELECTRIC LAMPS USUALLY ARE SUPPORTED, BAR, HANGERS WHICH ARE BARS FOR SUPPORTING OUTLET AND SWITCH BOXES, BAR SETS WHICH ARE BARS HAVING OUTLET OR SWITCH BOXES MOUNTED THEREON, FITTINGS FOR OVAL TUBES, AND BOX COVERS