Yes, it will fit any Sony e mount body, either full frame (a7..., a9...), or aps-c (like a6500, etc) 

Firstly, let's talk whether you need Nikon AI adapter ring or Nikon G adapter ring.
If your lens mount is AI, please choose AI one, if it is G please choose G one, there difference between them is G adapter ring with a aperture control ring.
If you want to use Nikon AI lens on this Nikon(G) adapter ring, it could be attached, but the aperture control ring could not be used，as there is a pin on Nikon G lens that could move the aperture control ring but no on AI lens.
So why have a separate adapter for the lenses with the 'G' designation? While the G lenses are the still the same physical F mount, the G indicator means there is no aperture dial on the lens itself. So while the G lenses will physically fit the standard F mount cameras and adapters, there is no way at all to change the f-stop on the lens. The adapters marked as Nikon G Mount are specifically made for those lenses in mind and have a dial built into them that allows you to control the lens iris from the adapter!
so here let's discuss the 4 items
KF06.068 AI mount, aluminum material
KF06.286 AI mount, with 1/4 Female thread screw for mounting onto the tripod
KF06.309 Ai mount, cooper material
KF06.070 G mount, aluminum material
 

1. please judge whether your lens could adjust the aperture there is only Nikon(G),also called AI(G) adapter ring has the aperture control ring, and is only for Nikon G lens,
   If you want to use nikon AI lens on this Nikon(G) adapter ring, it could be attached, but the aperture control ring could not be used as
   there is a pin on Nikon G lens that could move the aperture control ring but no on AI lens.
2. Some buyer mentioned could not adjust the aperture, actually this is because your lens does not have the aperture control function, If your lens does not have a manual aperture control ring, it will stop down to its smallest f/stop by default
3. Since there is no electronic contacted on our adapter ring, so could not transfer the aperture number to camera.

 

No. It has clicks in it. I only use this with Nikkor AI-S manual lenses, which are naturally clicked. However, if I remove the lens and just twist the ring on the adapter, it has regular clicks in it, finer than the one stop clicks on the Nikkor lenses I use. I bought my adapter in late Nov-early Dec 2016 

Yes it should work with the sony a6000. As long as the ka lens has an aperture ring on the lens and is not solely dependent on receiving aperture control from the body, this adapter should work fine with ka lenses. To my knowledge, there are no sony e mount to k mount adapters with electronic coupling so no lens control through the body (meaning aperture and focus are fully manual).