They are the analysis method created by the Federal Revenue Office – SRF through customs clearance, that is, once the Import Declaration (DI) has been registered and the customs clearance procedure has started, the DI is submitted to a tax analysis and selected for one of the inspection channels. This selection procedure is called parameterization. GREEN: The import selected for the green channel is cleared automatically without any verification, and the importer must come to the Customs Office only to withdraw the Import Voucher (exempt from documentary examination, merchandise verification, and delivery of the customs clearance instruction documents). YELLOW: The yellow channel means verification of the DI instruction documents and the information contained in the declaration (if no irregularity is found, after customs clearance is completed, verification of the goods is waived). RED: When selected to go through the red channel, in addition to documentary verification, there is a physical inspection of the goods (the goods will only be cleared after documentary examination, preliminary examination of the customs value, and verification of the goods). GRAY: If the DI is selected for the gray channel, the process includes documentary examination, physical verification of the merchandise and the application of a special customs control procedure to verify evidence of fraud, including with regard to the declared price of the imported merchandise, which begins with the registration of the import declaration (DI) in the Online Customs Authority System (Siscomex).