Both lines cover frozen trout fillets, but 0304825000 is the NESOI (not elsewhere specified or included) residual line, while 0304820000 is the primary enumerated line. In practice, CBP guidance and binding rulings determine which line applies to specific product presentations; importers with ambiguous product descriptions should seek a binding ruling for certainty.

Skin presence alone does not determine the tariff line under this heading — the key distinctions are block weight and processing intent. However, skin-on versus skin-off is a material commercial specification that should be accurately described on entry documentation to support any future audit or reclassification review.