This small box is a version of one of the most well-known puzzles designed by Constantin. The goal is to open it without forcing any element or using anything external to the box. Those are all the instructions.

As a hint (when players are desperate), it can be indicated that there is an object inside the box, and it will be key to opening it and overcoming the challenge.

Here is a link to the YouTube channel of Cuby where he solves it:

**Assembly Instructions:**

You will need 5 neodymium N52 magnets (preferably) of 5mmx2mm. These are integrated into the pieces, with slots included in the profiles to place them.

The assembly is very simple, although it requires some skill and caution with the glue.

**IMPORTANT!!!!** Pay attention to the polarity of the magnets. The top parts must attract each other when placing them in your printer as you make the pieces. The magnet for the key doesn't matter.

The rods, like the door, should remain loose to create confusion. Everyone expects the box to open through the door, but often the most logical answer is not the correct one.

And "logically" the back part should not be glued as that is where the box will open. Thanks to the magnets, it stays firm, making it seem unthinkable that this is the door.

If the back part is excessively hard to open, you will need to shave down the edges a bit.

Here are some photos and instructions that can facilitate the assembly.

Enjoy!