It's an insert for the Scream Board Game. It fits sleeved cards and can be stored vertically.

The original insert was ok, but there's too much shuffling involved, so I made this one that fits sleeved cards. I also didn't like to keep building the knife every time we played, so you can fit it built. I kept the plastic piece to store the Ghost Face mini.

Just print all 3 parts and build it like the picture.