1. The case was heard on 18-5-1983.

2. The appellants imported aluminium foil laminated with polyethylene film. The goods were assessed under Heading 76.03/04(2) of the Customs Tariff Act, 1975 and customs duty of 100% plus auxiliary duty of 20% plus countervailing duty of 33.6% was charged thereon. The importers filed an application for refund claiming re-assessment at the rate of 27.5% customs duty plus 5% auxiliary duty. They based their claim on the authority of notification No. 170/79-Cus, dated 24-7-79. The subject goods in this case were imported on 4-5-79, i.e., about 2 1/2 months earlier than the Issue of the notification relied upon by the appellants and the Assistant Collector, therefore, rejected their claim on the ground that the aforesaid notification was effective only from the date of its issue and it could not be applied retrospectively to the subject goods. At the appeal stage, the appellants relied instead on notification No. 67/79-Cus., dated 15-3-79. The Appellate Collector rejected this claim also on the ground that notification No. 67/79-Cus. covered only plain aluminium foil and did not cover laminated aluminium foil. The appellants filed a revision appl