An electric guitar, which requires electronic amplification to produce its characteristic sound, falls under heading 9207 (instruments whose sound is produced or amplified electrically) rather than the acoustic string-instrument heading 9202. If the instrument can produce audible sound acoustically and merely has a pickup added, classification may differ — a binding ruling from CBP is advisable for borderline cases.

Heading 9209 covers parts and accessories specifically for musical instruments — including strings, reeds, tuning pegs, metronomes, and tuning forks. However, if a part is more specifically described by another chapter (for example, electronic components), the Section notes and General Rules of Interpretation govern which heading applies.