This is one that nobody has heard of. There is also no mention of it in Waits and a Google search doesn't find anything. It was only blind luck that I found it.
I'm not actually even sure if it was sold as a Grant Hammond, but due to the lack of any other information, I've named after the patent holder.

The adjustment mechanism is a spring shim, like the Hospital / XOXO Hospital XOXO except that the shim is not attached and as a result is a 4-piece. This of course gives you the option to use it as a normal razor as well.

The oddity about it is that there are no manufacturers markings anywhere. The only markings on the razor are "MADE IN USA", the patent number and the graduation scale on the bottom of the base plate. The patent was granted on 22 January 1946 under patent number US2393366 and is in the same time period as the various "XOXO" razors out there so they would have been competing for the same audience.

The handle is aluminium and the head is "heavier" in comparison - so could be Zinc or Brass. There is no plate loss so I can't tell.

How does it shave?
Most closed it's a mild shaver.
If its opened between about ½ and ¾ of a turn it's a medium shaver. With some work you will get to a BBS.