A Post-It box where the stencil for the to-do list can be placed inside. It was created for 76x76mm Post It's. A 70x70mm version has also been uploaded. 
The hinge is the same for both (there are 2 version. One has the same dimensions as the hole and the other is slightly narrower to fit better). 
It has also only been tested with PLA. I can't say anything about other materials.

Assembly instructions:

1. Check whether both hinges fit into the recess. If necessary, rework with a file or knife so that it fits in at least a few millimeters. Do not put it in completely!
2. Both hinges should be inserted into the recess in the ceiling. This can be a little fiddly. It is best to insert them at an angle from the side. 
   (The design means that the cover cannot be removed so easily later).
3. Both hinges should be inserted into the recess in the lid. This can be a little fiddly. It is best to insert them at an angle from the side. 
   (Due to the design, the lid cannot be removed so easily later. You can also test whether it can be pushed on with pressure. This was initially planned. However, I had no confidence in it when printed out).
4. Insert the hinges slightly into the box and press them in with the lid. The closed cover should seal the entire area. (except for the little bit at the back)

Maybe I'll create a slightly smaller box one day. I also thought about whether the template could perhaps be stored in the lid? Maybe I'll do that one day or maybe you will? :D