This was a really interesting case.
I really loved mine when I used mine during that very last phase before COVID hit.
You can fit two hardcover A5 notebooks in it, plus room for three pens and a room where you can fit your Field Notes etc.
If Nock Co had continued I'd love to see more versions of this case. Like one that fitted more notebooks etc. I really loved having this single thing that fitted two of the three notebooks I used to carry in those days. And it served like this thing that fitted almost all the writing stuff I used most of the time.
Instead of finding my pens, then my Field Notes, then my bullet journal notebook, then my writing notebook. You know the drill.