SEZ Unit Tax Deduction permits phased export profit exemptions with conditional reinvestment tied to qualifying machinery use. Newly established SEZ Units may claim phased deductions for export derived profits and may credit a portion of profits to a Special Economic Zone Re investment Reserve Account to finance acquisition of machinery or plant first used within three years. Reserve amounts must be utilised for qualifying business purposes and are disallowed or deemed taxable if used otherwise or not invested within the prescribed period. Deductions require specified disclosures and timely return filing; export receipts must be realised in convertible foreign exchange and export profits are apportioned to export turnover relative to total turnover.