A watch movement is generally defined by its small size and the number of jewels or functional components meeting schedule-specific thresholds. Clocks housing movements that meet those criteria are classified under watch-movement headings even if the finished article looks like a conventional clock. Importers should review the applicable schedule notes carefully and consult a licensed customs broker to confirm classification.

Instrument panel clocks — designed for vehicle dashboards and similar applications — are carved out into their own classification, reflecting different end-use sectors and potentially different duty treatment. A clock with a watch movement intended for automotive OEM use may need to be classified elsewhere, so end-use documentation is important.