through the Nikon F-Mount - the difference between an AI lens and an AI-S lens
Nikkor 50mm f/1.4 Ai-S & 50mm f/1.2 Ai-S Standard Lenses - Version History in Ai-S Nikkor- Part VI
Lens Adapter Ring For Nikon F (non-ai, Ai, Ais) Lens To For Canon Eos Ef Ai-eos 550d 60d 5d3 700d 7d 50d 5d2 6d Brass Silver - Lens Adapter - AliExpress
Repair: Nikkor 35mm f/2 Ai-S | Richard Haw's Classic Nikon Repair and Review