8483.90.70.00 - Parts of articles of subheading 8483.20

This HTS category, 8483.90.70.00, specifically covers parts of articles that fall under subheading 8483.20, which pertains to ball or roller screw mechanisms. Therefore, this classification is intended for components and spare parts designed to be incorporated into or replace parts of ball or roller screws used for transmitting motion, such as lead screws, ball screws, and roller screws, along with their associated nuts and housings. Examples of such parts could include the recirculating balls or rollers themselves, specialized nuts designed for these screw mechanisms, or particular components of the screw shaft that are not classified as complete screws.

This category is distinguished from its sibling, 8483.90.80, which encompasses "Other" parts of transmission elements not specifically enumerated elsewhere. While 8483.90.70.00 is narrowly defined for parts of ball or roller screw mechanisms, 8483.90.80 serves as a residual category for all other parts of toothed wheels, chain sprockets, and other transmission elements that do not fit into the more specific classifications, including parts of gears, flywheels, pulleys, clutches, and shaft couplings. The key differentiator lies in the precise origin and function of the part: if it is integral to a ball or roller screw assembly, it belongs here; otherwise, it likely falls under the broader "Other" category.

As a leaf node, this HTS category does not have further subcategories. Classification into 8483.90.70.00 requires that the part in question be demonstrably intended for use within the ball or roller screw mechanisms outlined in subheading 8483.20. Importers should carefully consider the design, intended function, and material composition of the part to ensure it meets the specific criteria for inclusion under this heading, rather than being classified as a general mechanical part or a complete article.