Customs officer hierarchy under the Act defines graded appointments, including appellate, preventive, audit, and intelligence designations. Section 3 of the Customs Act classifies officers of customs into specified grades for administering the Act, including principal chief commissioners, chief commissioners, principal commissioners, commissioners, appellate officers, additional commissioners, joint commissioners, deputy commissioners, and assistant commissioners, with preventive, audit, and revenue intelligence designations where stated. It also authorises appointment of such other class of officers of customs as may be appointed for the purposes of the Act.