Customs duty cap limits excess ad valorem duty on specified tariff items upon import under a ministerial exemption. The Central Government issues a ministerial exemption under the Customs Act, 1962, exempting goods of Heading Nos. 80.03 to 80.07 from that portion of the ad valorem duty specified in the First Schedule to the Customs Tariff Act, 1975 which exceeds 40 per cent, thereby capping the effective customs duty on imports of those tariff items.