Duty exemption schemes enable duty free import for export production, subject to SION, actual user and value addition requirements. Chapter 4 provides duty exemption and remission mechanisms for exporters through Advance Authorisation and DFIA, governed by SIONs, self ratification or Norms Committee fixation. Authorisations require pre import and actual user compliance, specific input endorsement in shipping documentation, minimum value addition, and are subject to audits and recovery for misdeclaration. DFIA differs by post export issuance and exemption limited to Basic Customs Duty. The RoDTEP rebate scheme issues transferable electronic scrips to refund specified un refunded duties subject to notified rates, exclusions, audit and budgetary controls.