8477.90 - Parts:

HTS code 8477.90 encompasses all parts and accessories specifically designed for use with the machinery classified under heading 8477. This heading broadly covers machinery for working rubber or plastics, or for manufacturing products from these materials, which are not elsewhere specified in Chapter 84. Therefore, 8477.90 is a residual category for components that, while essential to the functioning of 8477 machinery, are not complete machines themselves.

This category is distinct from its sibling HTS codes, which classify the complete machines themselves (e.g., injection-molding machines, extruders, blow-molding machines). While those codes identify the apparatus for processing rubber and plastics, 8477.90 focuses solely on the individual components and replacement parts for these apparatuses. It serves as the "parts thereof" provision for the entire heading 8477.

The subcategories within 8477.90 further break down these parts based on their specific function and type. For instance, 8477.90.25 covers major structural components like bases and platens, while 8477.90.45.01 specifically addresses screw assemblies crucial for extrusion and injection processes. 8477.90.65.00 details hydraulic assemblies, and 8477.90.86 serves as a residual category for all other parts not specifically enumerated. These subdivisions facilitate more precise classification of the diverse components that make up the complex machinery covered by heading 8477.