673: Flat-rolled prod., iron, non-alloy steel, not coated

6731: Flat-hot-rolled, thickn.:<3mm=>275mpa, >3mm=>355mpa 6732: Flat-hot-rolled products, iron or non-alloy steel 6733: Flat-cold-rolled, thickn.:<3mm=>275mpa, >3mm=>355mpa 6734: Flat-cold-rolled products, not coated or clad, iron 6735: Flat-roll. products, iron or non alloy steel, n.e.s. 673: Flat-rolled prod., iron, non-alloy steel, not coated