Customs duty exemption for imported raw wool and wool waste caps payable duty to a specified ad valorem rate. The Central Government exempts imported raw wool under heading 51.01 and waste of wool (including yarn waste and garnetted stock) under headings 51.03 and 51.04, in the First Schedule to the Customs Tariff Act, 1975, from so much of the customs duty leviable thereon as is in excess of the amount calculated at the rate of thirty per cent ad valorem.