… Lenses, prisms, mirrors and other optical elements, of any material, mounted, being parts of or fittings for instruments or apparatus, other than such elements of glass not optically …
Explanatory notes
… Lenses, prisms, mirrors and other optical elements, of any material, mounted, being parts of or fittings for instruments or apparatus, other than such elements of glass not optically … the articles referred to in Items (B), (C) and (D) of the Explanatory Note to heading 90.01 when in a permanent …