This video, titled "ダンボールのダイアル式金庫 　[Dial Combination Safe　(cardboard)]," was released by "Makocchio Noto."

It introduces a dial safe made of cardboard, and the video shows how it's opened.
The cardboard used is usually used for storing vegetables and other items.
The safe is pretty impressive considering it's just cardboard and other materials you can find lying around.
The creative ideas of the maker are remarkable.
It really helps you understand how deep manufacturing goes.