In Portuguese Import Tax is named Imposto sobre a Importação and often referred to by the abbreviation II.
II is one of the components of the Brazilian customs taxes, just like IE.
Import duties are charged when foreign products enter the country. The taxpayer is usually the importer, but in some cases the taxpayer could be the buyer. The function of import taxes is purely economic or regulatory and it's different for each good. The values of the II rates can be found in the Tarifa Externa Comum, also known as TEC/NCM, the Common External Tariff established by Mercosur.
TEC establishes the non-existence of Import Tax (zero rate) to trade activities between Mercosur members, but when imports involves a third country – that's not a member – TEC is applied. The tax rate varies from 0 to 20%, depending on the goods involved in the transaction.