Heading 9002 · Section XVIII
9002 Lenses, prisms, mirrors and other optical elements, of any material, mounted, being parts or fittings for instruments or apparatus, other than such elements of glass not optically worked
Subheadings 4
9002.11 Objective, for cameras, projectors or photographic enlargers or reducers, mounted, being parts or fittings for instruments or apparatus, of any material (excluding glass not optically worked) 9002.19 Objective, (other than for cameras, projectors or photographic enlargers or reducers), mounted, of any material (excluding elements of glass not optically worked) 9002.20 Mounted as parts or fittings for instruments or apparatus, of any material (excluding elements of glass not optically worked) 9002.90 N.e.c. in heading no. 9002 (e.g. prisms and mirrors), mounted, being parts or fittings for instruments or apparatus, of any material (excluding elements of glass not optically worked)
For Indian shipping bills you need 8 digits. These six-digit codes are the international HS 2022. India's ITC(HS) classification (DGFT) and Customs Tariff (CBIC) add two more digits for the national tariff line, so pick the 8-digit line under your 6-digit code there, and confirm with your customs broker for anything borderline.