"The products at issue in this case consist of a variety of metal fasteners that Rocknel imported from Japan in 1997. The fasteners, which are fabricated from metal alloys, have rod-shaped bodies and hexagonally shaped heads. Their bodies are fully or partially threaded. Rocknel has admitted that the fasteners were designed to be installed in holes of assembled parts and that the fasteners were designed to be tightened or released by turning their heads.
...
The Customs Service liquidated the fasteners under subheading 7318.15.80 of the Harmonized Tariff Schedule of the United States (“HTSUS”). Subsequently, Rocknel filed a protest, claiming that the fasteners should have been classified under HTSUS subheading 7318.15.20."
(15.80 is screws, 15.20 is bolts)
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"The court concluded that the tariff schedule required that the terms “bolt” and “screw” be given mutually exclusive definitions.
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Because Customs had looked to the ANSI Specification as the source of the definitions of “bolt” and “screw” for tariff classification purposes, and because Rocknel had admitted that under the ANSI Specification the fasteners at issue in this case would be classified as screws and not bolts, the court granted summary judgment to Customs upholding the agency's classification of the fasteners."