A movement set (911011) contains all the parts needed to constitute a complete watch movement but has not yet been assembled. Once those same parts are fully assembled and functional, the article moves to heading 9108. The distinction matters at entry because the two headings can carry different duty rates.

An assembled movement that lacks components necessary for it to be complete falls under 911012 as an incomplete but assembled watch movement, not under 9108. Importers should document which components are absent, as customs may request technical specifications to confirm the incomplete status.