I liked Jan 3D's toolbox design, it's one of the first thing I printed when I got my P1S.

however, i find some spaces are empty, and having difficulty storing other items, such as this filament cutter in this toolbox. i believe the original design showing those cutter being left loose in the upper left corner, but I'm not so comfortable leaving sharp edges in an semi-open space, so i designed this simple insert to go into one of the nozzle wipe holder slots, and it will hold 3 pcs of filament cutter.

the cutout is slightly longer than the blade length, so the sharp edge will not be bumping against anything while in storage and therefore stay sharp.