Essential replaceable filter membrane classified as machinery part under Chapter 84, with notification benefit upheld.

Membrane elements used inside imported filter units were treated as essential, replaceable parts of a composite filtering and purifying system rather than as consumable filter media classifiable by constituent material. Because the item functioned only within reverse osmosis and nanofiltration apparatus, it fell under Chapter 84, specifically Tariff sub-heading 8421.99, as parts of filtering and purifying machinery. The analysis also relied on Harmonized System classification guidance supporting replacement filter cartridges under Heading 8421.99 regardless of the filtering medium's material. On that basis, the claimed benefit of Notification No. 62/94 and Notification No. 172/89 was available.

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Issues: Whether membrane elements used inside imported filter units were classifiable under CTH No. 3926.90 as filter elements of polyamide, or under Tariff sub-heading 8421.99 as parts of filtering and purifying machinery, and whether the benefit of Notification No. 62/94 and Notification No. 172/89 was available.

Analysis: The item was not treated as a mere consumable filter medium such as paper or cloth, but as an essential part of a filtering and purifying system. The evidence showed that it functioned only as part of a composite filtration apparatus, including reverse osmosis and nanofiltration systems, and was vacuum sealed and replaced over time to keep the system operating. On that basis, the item was held to fall within Chapter 84. Reliance was also placed on the classification opinions under the Harmonized Commodity Description and Coding System, which supported classification of replacement filter cartridges under Heading 8421.99 irrespective of the material used as the filtering medium.

Conclusion: The item was correctly classifiable under Tariff sub-heading 8421.99, and the Revenue's challenge to the grant of the notification benefit failed.

Ratio Decidendi: Where a product functions as an essential and replaceable part of a filtering system, it is classifiable as part of filtering and purifying machinery under Chapter 84 rather than by its constituent material.

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