Customs tariff amendment revises the duty entry for spent catalysts and ash containing precious metals under existing notification. The notification amends Notification No. 50/2017-Customs by substituting the entry in column (4) against S. No. 364A with '10%', thereby altering the tariff entry applicable to spent catalysts and ash containing precious metals under the Table of miscellaneous exemption notifications, pursuant to powers under the Customs Act and the Customs Tariff Act.