Stamping foils are designed for dry transfer by heat and pressure — the metallic or pigmented layer releases from a carrier film onto the substrate during the stamping process. Decorative laminates are bonded permanently to a substrate and classified elsewhere (typically Chapter 39 or 48 depending on material). Adhesive films that transfer by pressure alone without heat may also fall outside heading 3212. The transfer mechanism and the product's presentation in rolls or sheets for stamping machines are the key classification indicators.

Stamping foils of Chinese origin are subject to Section 301 tariffs, which add to the standard duty rate. Taiwan-origin foils are not subject to Section 301, making Taiwan an attractive alternative source — and Taiwan is in fact the leading US supplier under this heading. Importers should ensure country-of-origin documentation is robust, as the substantial transformation rules for foil processing can be complex when base film and metallization occur in different countries.