Water filter classification turns on filtration function; incidental purification did not defeat excise exemption.

The product was treated as a water filter because its function was found, on factual examination, to be filtration of water. The incidental removal of suspended matter and bacteria through that filtration did not create a separate purifying process, so the apparatus remained within the class of water filters. On that basis, the exemption under the relevant central excise notification was attracted, and the corresponding later notification supported the same treatment.

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Issues: Whether the product 'hydrapure' was classifiable as a water filter entitled to exemption from duty under the relevant central excise notifications.

Analysis: The product was found on the factual examination to perform the function of a water filter. The mere fact that the filtration process also resulted in purification by removing suspended materials and bacteria did not take the apparatus out of the class of a water filter, since no separate purifying process apart from filtration was shown to exist. The exemption claimed was therefore attracted under the notification, and the later corresponding notification was also held to support the same treatment.

Conclusion: The product was held to be a water filter entitled to exemption from duty, and the assessee succeeded.

Ratio Decidendi: Where an apparatus primarily filters water and purification occurs only as an incident of filtration, it remains a water filter for the purpose of exemption under the relevant notification.

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