I have two Nikor sheet-film tanks now, one much older than the other. The newer one has a slightly larger, better tank with a brushed finish, and the older one has a slightly smaller tank with a shiny finish, and the caps are not interchangeable--neither the large daylight cap nor the small cap for the spout, so be aware of that, if you're hunting for parts. The reels are interchangeable, though.

One has a metal band, and one doesn't, but I've used a rubber band, and it works fine.