GI (Galvanized Iron) square tubes, an essential building and industrial material as referenced by sources like ISCON, HTL, Surya, and Apollo. The tubes are made of steel, treated with a thick layer of protective zinc coating. The primary visual characteristic is the distinct spangled pattern on their surface—the mottled, crystalline look of the solidified zinc. This coating is visibly rugged and utilitarian, with variations in the spangle size and occasional industrial markings, scratches, and minor corrosion spots from storage, accurately representing a standard industrial product used for corrosion resistance. The metal appears heavy and durable, and the ends of the tubes clearly show the thickness of the hollow section walls.
