Zero-rated supply treatment allows SEZ units duty-free procurement subject to prescribed documentary proof and export endorsement. SEZ units and Developers may procure a broad range of goods from the Domestic Tariff Area or specified export-oriented units without payment of duty, subject to SEZ Rules and import prohibitions. DTA suppliers must clear such supplies as zero-rated under IGST/Central Excise procedures (bond, undertaking or refund route) or as duty-paid with rebate, using prescribed documentary cover. Goods admitted on export entitlement require an assessed bill of export; the authorized officer's endorsement of full admission serves as proof of export and must be sent to the DTA supplier's GST/Central Excise officer within forty-five days or tax demand may follow.