Zero rated supplies under IGST: exporters may export under bond or pay IGST and claim input tax refunds. Exports and supplies to SEZs are zero rated supplies under IGST. Exporters may either export under bond without paying IGST and claim refund of unutilized input tax credit, or export on payment of IGST and claim refund of IGST paid. SEZs retain duty-free import status. EOUs, Advance Authorisation and EPCG holders retain Basic Customs Duty exemptions but must pay IGST on imports and use ITC; Advance Authorisation holders may claim refund of unutilized ITC after export, EPCG holders may not. Scrips cannot be used to pay GST.