Left: 400mm f/3.5 ED~IF in Ai-S mount with aftermarket CPU and contacts added. On the right, the 300mm f/4.5 ED~IF in Ai-S mount.

Uploaded to TPF on 2014_0415 in this thread http://www.thephotoforum.com/forum/nikon-lenses/356712-nikkor-ai-s-lenses-post-your-experiences-them-all-them.html