12 FERROUS METAL TUBULAR PRODUCTS AND PIPE ARCHES-NAMELY, BOTH CORRUGATED AND UNCORRUGATED, LINED AND UNLINED, COATED AND UNCOATED, SEAMLESS, WELDED, LOCK-SEAMED, BOLTED AND RIVETED, PERFORATED AND UNPERFORATED, FOR USE IN DRAINAGE, IRRIGATION, TUNNELING, TILING AND ALLIED FIELDS; STEEL BUILDINGS AND ELEMENTS THEREOF; TANKS FOR STORAGE AND CHEMICAL PROCESSING; FABRICATIONS FOR USE IN HIGHWAY CONSTRUCTION AND THE LIKE-NAMELY, GUARD RAILS, RETAINING WALLS, AREA WALLS, SNOW FENCES, [ POSTER PANELS, ] BRIDGE RAIL AND BRIDGE PLANK; [ WATER CONTROL GATES; PANELS USED IN RAILROAD CAR CONSTRUCTION; ] CONVEYOR COVERS, AND STRUCTURAL SHAPES AND JOISTS