7214.91.00.90 - Containing by weight 0.6 percent or more of carbon

This HTS classification, 7214.91.00.90, specifically identifies bars and rods of iron or nonalloy steel that have been processed through forging, hot rolling, hot drawing, or hot extrusion, and subsequently twisted. Crucially, these products are distinguished by their carbon content, which must be 0.6 percent or more by weight. This category encompasses items with a rectangular (but not square) cross-section, as indicated by its parent heading.

The primary distinction for goods falling under 7214.91.00.90 lies in the defined carbon threshold. Unlike sibling categories that classify products with lower carbon percentages (less than 0.25% and between 0.25% and 0.6% respectively), this node targets materials with a higher carbon composition. This higher carbon content can influence the material's properties, such as hardness and strength, which are key considerations in its industrial applications.

As this is a leaf node within the HTS structure, there are no further subcategories. Therefore, classification under 7214.91.00.90 is definitive once the criteria of being a forged, hot-worked, or hot-extruded bar or rod with a non-square rectangular cross-section and containing 0.6% or more carbon by weight are met. Examples could include reinforcing bars for construction or structural components where specific strength characteristics are required.