Both strip and foil are flat-rolled products of limited width, but foil is generally understood to be very thin — typically under 0.15 mm — while strip covers thicker gauges. The HTS does not always draw a bright-line thickness threshold between them, so the commercial description and the manufacturer's specification are the primary guides. When thickness is borderline, a binding ruling from CBP provides certainty.

Yes — 750610 (unalloyed) and 750620 (alloy) carry separate tariff lines and may have different normal trade relations rates. Additionally, any antidumping or countervailing duty orders in force attach at the subheading and country level, so the alloy designation directly affects the duty calculation. Importers should confirm the alloy composition against the applicable mill certificate before filing entry.