The HTS distinguishes refined copper from copper alloys based on defined composition thresholds — for example, brass (copper-zinc alloys) and bronze (copper-tin alloys) fall under different HTS headings than unalloyed copper. The specific alloy percentages, product form (rod, tube, sheet, wire), and whether the product is in coil or straight lengths all influence the correct 10-digit subheading, and misclassification can result in incorrect duty assessment or trade-remedy exposure.

Electrical and electronics manufacturing is the dominant end-use, consuming copper rod and wire for conductors and connectors. Construction drives demand for copper tube used in plumbing and HVAC systems, while automotive and industrial equipment sectors consume brass and bronze rod for machined fittings and bearings. Ammunition manufacturing is also a significant consumer of brass strip and cup stock.