Customs exemption caps basic duty for specified Chapter 82 imports at an ad valorem rate. The Central Government, exercising power under section 25(1) of the Customs Act, 1962, exempts all goods under heading nos. 82.01-82.11 of the First Schedule to the Customs Tariff Act, 1975 from so much of the basic customs duty as exceeds the amount calculated at an ad valorem rate of 40 percent, thereby capping the effective basic duty on those imported goods.