The F2 accepts all lenses with the Nikon F bayonet mount (introduced in 1959 on the Nikon F camera), with certain limitations or exceptions depending on the F2 version. The later F2A and F2AS Photomic variants (see below) require lenses supporting the Automatic maximum aperture Indexing (AI) feature (introduced in 1977). The manual focus Nippon Kogaku made AI lenses were the Nikkor AI-S, Nikkor AI and Nikon Series E types. The AF-S Nikkor, AF-I Nikkor, AF Nikkor D and AF Nikkor autofocus lenses are also AI types. The original Nikkor "non-AI" (introduced before 1977) lenses, will mount but require stop down metering. Nippon Kogaku had a service to retrofit non-AI lenses with a new aperture ring with the AI feature to produce "AI'd" lenses, but this service ended decades ago.