Heading 7904 covers semi-finished wrought shapes — bars, rods, profiles, and wire — that have not yet been further worked into a specific article. Once the zinc has been fabricated into a recognizable finished article (such as a fitting or a decorative piece), it moves to the residual articles heading. The key test is whether the product retains the character of a semi-manufactured shape.

Zinc wire under 7904 is a base-metal product classified by its material composition. Electrical conductors are classified in the chapter covering insulated wire and cable regardless of the conductor metal. Bare zinc wire used as a conductor would still fall here unless it is insulated or assembled into a cable, in which case the electrical-wire chapter governs.