A storage case for tank gun cartridges. From the description alone, it's hard to imagine what it is, but it looks like this.
The diameter is about 15.8cm. There are other uses for cylindrical boxes, but with something this thin, I can't think of any other uses for it other than putting posters in it. However, the texture of the material and the lettering look really nice. I hope people will enjoy displaying it.
Tank gun cartridge case