7318.15.80.20 - Set screws

This classification, HTS 7318.15.80.20, specifically identifies "Set screws" when they are made of iron or steel, are threaded articles, and fall under the broader category of "Other screws and bolts, whether or not with their nuts or washers," and "Other" further breakdowns. Set screws are characterized by having a head that is not designed to be externally driven, often being recessed or flush when installed. Their primary function is to secure an object within or against another object by exerting pressure through a point or blunt end, effectively preventing relative motion.

Distinguishing this category from its immediate sibling, which is also under "Other:", relies on the specific physical characteristics of the screw. While other sibling categories might encompass screws with different thread diameters or specific head types not considered "set screws," this node is precisely for set screws where the shank or thread diameter is 6 mm or more. This diameter threshold is a critical differentiator within the broader "Other screws and bolts" grouping.

As this is a leaf node in the HTS classification, there are no further subcategories to introduce. Therefore, the classification is complete at this level, with "Set screws" having a diameter of 6 mm or more representing the most specific grouping within this branch of the Harmonized Tariff Schedule. Classification within this code necessitates confirmation of the article's nature as a set screw and its corresponding thread or shank diameter.