For hot-rolled coils (600 mm or more wide), the heading uses multiple thickness bands: over 10 mm (721911), 4.75–10 mm (721912), 3 mm to under 4.75 mm (721913), and under 3 mm (721914). Accurate thickness measurement from the mill certificate is essential because each band can carry a different duty rate and may be covered by different antidumping order scopes.

Hot-rolled coils have a scaled or pickled surface and are typically used where tight tolerances are not required, while cold-rolled products offer tighter thickness tolerances, smoother surfaces, and better formability for precision applications. The distinction matters for classification because the subheadings are separate, and antidumping orders often cover one rolling method but not the other.