This heading covers complete or incomplete metal structures, as well as parts of structures. For the purpose of this heading, these structures are characterised by the fact that once they are put in position, they generally remain in that position. They are usually made up from bars, rods, tubes, angles, shapes, sections, sheets, plates, wide flats including so-called universal plates, hoop, strip, forgings or castings, by riveting, bolting, welding, etc. Such structures sometimes incorporate products of other headings such as panels of woven wire or expanded metal of heading 73.14. Parts of structures include clamps and other devices specially designed for assembling metal structural elements of round cross-section (tubular or other). These devices usually have protuberances with tapped holes in which screws are inserted, at the time of assembly, to fix the clamps to the tubing.
Apart from the structures and parts of structures mentioned in the heading, the heading also includes products such as:
Pit head frames and superstructures; adjustable or telescopic props, tubular props, extensible coffering beams, tubular scaffolding and similar equipment; sluice-gates, piers, jetties and marine moles; lighthouse superstructures; masts, gangways, rails, bulkheads, etc., for ships; balconies and verandahs; shutters, gates, sliding doors; assembled railings and fencing; level-crossing gates and similar barriers; frameworks for greenhouses and forcing frames; large-scale shelving for assembly and permanent installation in shops, workshops, storehouses, etc.; stalls and racks; certain protective barriers for motorways, made from sheet metal or from angles, shapes or sections.
The heading also covers parts such as flat-rolled products, “wide flats” including so-called universal plates, strip, rods, angles, shapes, sections and tubes, which have been prepared (e.g., drilled, bent or notched) for use in structures.
The heading further covers products consisting of separate rolled bars twisted together, which are also used for reinforced or pre-stressed concrete work.