Customs duty cap limits basic duty on Chapter 44 timber products, exempting any levy above the prescribed ad valorem rate. The Central Government, invoking powers under the Customs Act, exempts all goods under heading Nos. 44.08-44.21 of the First Schedule to the Customs Tariff Act from so much of the basic customs duty as is in excess of 55% ad valorem by Notification No. 59/90-Cus dated 20-3-1990.