Special duty of excise on specified goods imposed as an additional levy with proceeds retained by the Union. The section prescribes a special duty of excise on specified goods assessed under the First Schedule to the Central Excises Act, levied in addition to existing excise duties at prescribed percentage rates on grouped items; such special duties are for the Union and not distributable to the States, and the Central Excises Act and its rules, including refunds and exemptions, apply to the levy and collection insofar as practicable.