Chapter notes
1. This Chapter does not cover:
(a) Clock or watch glasses or weights (classified
according to their constituent material);
(b) Watch chains (heading 71.13 or 71.17, as the case
may be);
(c) Parts of general use defined in Note 2 to Section
XV, of base metal (Section XV), or similar goods
of plastics (Chapter 39) or of precious metal or
metal clad with precious metal (generally heading
No. 71.15); clock or watch springs are, however,
to be classified as clock or watch parts (heading
91.14);
(d) Bearing balls (heading 73.26 or 84.82, as the case
may be);
(e) Articles of heading 84.12 constructed to work
without an escapement;
(f) Ball bearings (heading 84.82); or
(g) Articles of Chapter 85, not yet assembled together
or with other components into watch or clock move-
ments or into articles suitable for use solely or
principally as parts of such movements (Chapter
85).
2. Heading 91.01 covers only watches with case wholly of
precious metal or of metal clad with precious metal, or
of the same materials combined with natural or cultured
pearls, or precious or semi precious stones (natural,
synthetic or reconstructed) of headings 71.01 to 71.04.
Watches with case of base metal inlaid with precious
metal fall in heading 91.02.
3. For the purposes of this Chapter, the expression "watch
movements" means devices regulated by a balance wheel
and hairspring, quartz crystal or any other system
capable of determining intervals of time, with a dis-
play or a system to which a mechanical display can be
incorporated. Such watch movements shall not exceed 12
mm in thickness and 50 mm in width, length or diameter.
4. Except as provided in Note 1, movements and other parts
suitable for use both in clocks or watches and in other
articles (for example, precision instruments) are to be
classified in this Chapter.