This one:

I've had two. This version, and the single coated Nikkor-H version. Both perform pretty much identically. Both lenses were factory AI'd, when I got them. Not sure if my current one (the one depicted above on my F2A) was originally sold with the AI conversion ring or not, but, that doesn't matter to me. It is my favorite lens, and, since it's the MF version, it takes 52mm filters.