Customs classification of calorimeter parts must rest on technical evidence and clear reasons before shifting headings.

Classification of short-shipped parts and accessories of a calorimeter depended on whether they were integral to the main article or separately classifiable under the relevant section notes, chapter notes and headings. Because the calorimeter was already accepted under Heading 90.25, a later shipment of missing parts could not be shifted to a different heading without technical material and clear reasons. In the absence of catalogue evidence and satisfactory justification for the new classification, the impugned classification could not stand and the matter was remitted for fresh determination; the refund rejection was set aside to that extent.

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Issues: Whether the short-shipped parts and accessories of a calorimeter were required to be classified under the same heading as the main calorimeter, and whether the classification adopted in the impugned order could stand in the absence of technical literature and clear reasons.

Analysis: The calorimeter itself had been accepted under Heading 90.25, and the short-shipment of certain parts was not disputed. A subsequent shipment of missing parts could not be mechanically classified differently merely because it arrived later; the decisive question was whether the items were essential or integral to the calorimeter or were separately classifiable parts or accessories under the relevant section notes, chapter notes and headings. The record did not contain the technical literature needed to determine the nature of the printer and industrial package, and neither side could explain their exact character. The reasons given for shifting the classification were also found to be unsatisfactory, particularly because the calorimeter is specifically covered by Heading 90.25 and the invocation of other headings was not properly justified.

Conclusion: The impugned classification could not be sustained on the existing material, and the matter had to be sent back for redetermination on the basis of the catalogue, technical literature and any further evidence produced.

Final Conclusion: The appeal succeeded only to the extent that the rejection of the refund claim was set aside and the classification dispute was remitted for fresh decision.

Ratio Decidendi: Where the classification of missing or subsequently supplied parts depends on whether they are integral to a specifically classified main article, the authority must decide the issue on relevant technical material and chapter notes, and an unsupported change of classification cannot be sustained.

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