Central Excise exemption: water filters up to 40 litres under 8421.00 prescribed nil duty by tariff amendment. The Central Government amends the annexed table of Notification No.155/86 by substituting a new entry identifying goods under 8421.00 described as water filters of capacity not exceeding 40 litres and prescribing Nil duty for those goods, thereby granting a categorical excise exemption for the specified water filters.