[Rover]

Slightly trivial info:

 

Nikon F mount and Sony E mount are almost completely the same thing. You can fit made-for-E-mount things like adapter tubes and body caps on to a Nikon and it will go in and will even click-lock in place (although with a slight wobble). Trick is, it's about 120 degrees rotated. I don't recommend putting F mount lenses directly in front of a Sony though since protruding pins might damage your camera but even the rear lens caps are mostly interchangable. 

Thanks! I thought I was the only one who has been stating that, so doubt has crept into my mind that I might have had made this up. I thought I'd read that bellows and similar accessories make the most sense to share between the mounts.