9110 - Complete watch or clock movements, unassembled or partly assembled (movement sets); incomplete watch or clock movements, assembled; rough watch or clock movements:

HTS Code 9110 encompasses a variety of incomplete or unassembled components intended for the manufacture of watches and clocks. This category specifically includes complete watch or clock movements that are provided in an unassembled or partly assembled state, often referred to as movement sets. It also covers movements that are assembled but still considered incomplete, as well as rough, unfinished movements. The defining characteristic of items within this heading is their status as pre-manufacturing or intermediate stages of watch and clock movement production.

Distinguishing HTS 9110 from its siblings requires understanding the scope of Chapter 91 as a whole. While other headings in Chapter 91 might cover finished clocks and watches (e.g., Heading 9102 for wrist-watches and pocket-watches), or individual parts of movements (which would fall under different headings), 9110 focuses on the movement itself in its various stages of assembly before it becomes a functional, integrated unit within a complete timepiece. This heading is distinct from raw materials or basic components that have not yet been formed into a movement assembly.

The subcategories within 9110 serve to further refine the classification based on the intended application of the movement. The breakdown generally differentiates between movements specifically designed for watches versus those intended for clocks. This distinction is crucial for tariff purposes, as it reflects different manufacturing processes and market segments.