Customs exemption amendment substitutes tariff table entry for a specified schedule item, altering duty calculation methodology. The Central Government, exercising the power under sub section (1) of Section 25 of the Customs Act, 1962, amends Notification No. 136/86 Customs by substituting, in the Table annexed thereto, the entry in column (4) against Sl. No. 66D with a new tariff/duty specification as set out in Notification No. 308/87 Cus dated 9 9 1987.