… of or fittings for instruments or apparatus, other than such elements of glass not optically worked. …
Explanatory notes
… of or fittings for instruments or apparatus, other than such elements of glass not optically worked. ‑ … Mounted prisms for instruments or apparatus for physical or chemical analysis (polarimeters, etc.). (5) Mounted … or apparatus (for example, certain rear‑view mirrors, chimney or drain inspection mirrors, and special mirrors for …