Excise exemptions for specified machinery establish reduced duty rates for listed Chapter 84 goods under the Central Excise Tariff. Notification No. 155/86 uses rule 8(1) of the Central Excise Rules, 1944 to exempt or limit excise duty on specified goods under Chapter 84 of the Central Excise Tariff Act, 1985 by prescribing nil or reduced rates in a Table that matches tariff headings and product descriptions to corresponding duty rates or fixed per-unit duties.