8412.90.90.05 - Of linear acting engines and motors

This HTS category, 8412.90.90.05, specifically covers parts and components for linear-acting engines and motors. These are mechanical devices that convert fluid power (hydraulic or pneumatic) into linear motion. Examples of such parts include pistons, cylinder rods, seals, and housings designed exclusively for linear actuators, such as hydraulic cylinders, pneumatic cylinders, and similar reciprocating mechanisms. The classification hinges on the part's direct function within the linear motion generation process of these specific engine and motor types.

Unlike its sibling category 8412.90.90.15, which broadly covers "Other" parts of engines and motors not elsewhere specified within Chapter 84, this subheading is narrowly defined for parts dedicated to linear acting engines and motors. This means that if a part is integral to a device producing straight-line movement from fluid pressure, it belongs here, rather than in a more general "other" category. The distinction is crucial for accurate tariff application, focusing on the *type* of motion generated by the engine or motor to which the part belongs.

As this is a leaf node in the HTS classification structure, there are no further subcategories. Classification within this code is definitive for parts solely designed for and solely functioning within linear-acting engines and motors. The focus remains on the direct application and mechanical purpose of the component in achieving linear displacement through hydraulic or pneumatic power.