Width at the time of importation governs: if the strip is under 600 mm wide when it enters the US, it is classified in 7220 regardless of whether it was slit from a wider coil. The slitting operation itself does not change the rolling method classification (hot-rolled vs. cold-rolled), so the appropriate subheading within 7220 still depends on how the steel was rolled.

The mill certificate will state the rolling method. Hot-rolled strip is produced at elevated temperatures and typically has a scaled or pickled surface; cold-rolled strip is processed at room temperature after hot rolling and has a smoother, brighter finish with tighter thickness tolerances. If the certificate is ambiguous, the surface condition and tolerance specifications are secondary indicators.