Classification of circuit breaker parts turns on HSN notes: ready-to-fit insulating fittings fall under Heading 85.47.

Imported arc chamber insulators that are ready-to-fit and actually fitted to circuit breakers are classifiable as insulating fittings for electrical machinery or apparatus under Heading 85.47, not as insulators under Heading 85.46. The HSN Explanatory Notes distinguish insulators used to support or guide conductors from insulating fittings for apparatus, including parts of circuit breakers, where the article is designed for insulating purposes and may also serve another function. On that basis, the goods fall under sub-heading 8547.10 rather than 8546.20.

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Issues: Whether the imported arc chamber insulator, being a ready-to-fit part of a circuit breaker, was classifiable as an insulator under sub-heading 8546.20 or as an insulating fitting for circuit breakers under sub-heading 8547.10 of the Customs Tariff.

Analysis: The classification depended on the HSN Explanatory Notes to Headings 85.46 and 85.47. Heading 85.46 covers insulators used for fixing, supporting or guiding electric current conductors while insulating them, whereas Heading 85.47 covers insulating fittings for electrical machinery, appliances or apparatus, including parts of circuit breakers, where the article is wholly of insulating material or designed for insulating purposes even though it may also serve other functions. The imported item was found to be a part of the circuit breaker and a ready-to-fit article actually fitted to the circuit breaker. On that basis, it was treated not as a mere insulator but as an insulating fitting falling within Heading 85.47.

Conclusion: The imported goods were correctly classifiable under sub-heading 8547.10 and not under sub-heading 8546.20.

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