Exemption eligibility for DTA sales: imported inputs allowed if units prove DTA goods are wholly from indigenous raw materials. Benefit of Notification No. 8/97-CE may be granted to units using both imported and indigenous raw materials if they satisfy Central Excise authorities that inputs used for goods sold in the DTA were manufactured wholly from indigenous raw materials by maintaining records, permitting physical verification and, where necessary, fixing input output norms via a Cost Accountant; in cases of common inputs, non segregated lines, or indistinguishable products, the benefit should be denied to avoid misuse.