Rebate under Rule 18 permitted for supplies from domestic tariff area to special economic zones, subject to prescribed procedure. Rebate under Rule 18 of the Central Excise Rules is admissible on clearances from the Domestic Tariff Area to Special Economic Zone units; clearance of duty free material for authorised SEZ operations is effected under the SEZ Act and implemented through the excise rebate procedures, with field formations required to follow the existing administrative circular and prescribed documentation and procedural modifications for DTA SEZ supplies.