Auxiliary duty exemption for imported machinery parts limits duty to the rate applicable to the finished article when proven to customs. Exempts component parts of machinery imported for initial setting up, assembly or manufacture of specified articles from auxiliary customs duty to the extent such duty exceeds the rate applicable to the finished article when imported complete, conditional on the parts falling within the listed tariff headings or specified descriptions and on proof to the Assistant Collector of Customs that the parts are required for those purposes, subject to conditions in prior notifications and relevant notifications and rates for the finished article.