National customs tariffs contain a list of all products which can be imported.  Within the tariff, products are grouped according to the material they are made of, or according to the industrial sector to which they pertain either as input or as output materials (HS six-digit headings).  Within those product groups customs tariffs contain as many tariff lines as there are different levels of customs duties.  In other words, each duty rate is attached to a tariff line.

A tariff applying to goods imported within a limit in value or quantity.  A higher tariff applies to goods imported above the quota.

Conversion of border measures, other than ordinary customs duties, to tariff equivalents of non-tariff measures.  As part of the Uruguay Round Market Access for agricultural products, all non-tariff border measures were "tariffied" by participants before a tariff reduction was made.

See Tariffication.