Tin coating weight (expressed as a differential or equal coating designation in g/m²), temper grade (T1 through DR9), and surface finish (bright, stone, or matte) are the primary specification variables. These affect both the commercial grade and, in some cases, the applicable HTS subheading at the 10-digit level, so the mill certificate should clearly state all three parameters.

The steel substrate itself is not subject to FSIS or FDA import admissibility review as a raw material. However, downstream can manufacturers must ensure the tinplate meets FDA food-contact material standards (21 CFR) when used in food packaging. Importers of the raw coil do not face a mandatory admissibility inspection, but should retain mill certifications confirming coating composition for their customers' compliance records.