Pyrometer parts classification: thermocouple leads were treated as essential accessories, not insulated electric conductors.

Mineral insulated thermocouple leads, also described as compensating cables, were treated as not falling within Heading 85.44 because they did not function as insulated electric conductors transmitting electrical energy. The product transmitted thermo-electromotive force and was found to be an essential part of the pyrometer, without which the instrument could not operate. Applying the principle that goods used solely or principally with a particular instrument are classified with that instrument, the classification was aligned with Chapter 90. The goods were accordingly classified under Heading 90.25 as pyrometers and their parts and accessories, and the Revenue's classification was sustained.

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Issues: Whether mineral insulated thermocouple leads, also described as compensating cables, were classifiable under Heading 85.44 as insulated electric conductors or under Heading 90.25 as pyrometers and their parts and accessories.

Analysis: The product was used to connect the thermocouple to the pyrometer and transmit thermo-electromotive force, not electrical energy. Heading 85.44 covered insulated wires, cables and other insulated electric conductors, whereas the goods in question were not found to be conductors in that sense. The product was held to be an essential part of the pyrometer, without which the instrument could not function, and therefore fell within Chapter 90 under the rule that goods suitable for use solely or principally with a particular instrument are to be classified with that instrument. The earlier view treating the goods as insulated cables was not accepted, and the classification was aligned with the heading covering pyrometers.

Conclusion: The goods were not classifiable under Heading 85.44 and were correctly classifiable under Heading 90.25 as sub-heading 9025.00, in favour of Revenue.

Final Conclusion: The product was held to be classifiable with the pyrometer under Chapter 90 rather than as insulated electric cable under Heading 85.44, and the Revenue's classification was sustained.

Ratio Decidendi: A thermocouple lead that transmits thermo-electromotive force and functions as an essential part used solely or principally with a pyrometer is classifiable with the pyrometer under Chapter 90, not as an insulated electric conductor under Heading 85.44.

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