Auxiliary duty exemption on imported machinery parts limits levy to the duty rate applicable to the complete machinery article. Auxiliary duty is exempted on component parts imported for initial setting up, assembly or manufacture of specified machinery, provided importers prove necessity to the Assistant Collector of Customs and comply with prior notification conditions; the exemption limits payable duty to the rate applicable on the complete article, with the notification superseding an earlier one and enumerating covered tariff headings and specified items, including stated exclusions and voltage/current or power-based design conditions for certain electrical goods.