This is cover for PocketBook 626 ebook reader, inspired by original flip cover. It is slightly more thick (3mm vs. 2.5mm) to allow reliable printed hinges. Included STL file has sockets for 10x5x1.2 magnets but you can customize magnet size in source scad file.
It features space for optional magnets – they has to be inserted during the print though, either by manually pausing the print or using tool like Prusa's color print. When inserting magnets, it is strongly recommended to use glue, as most print heads contain ferromagnetic parts, which would cause magnets to pop out of print and stick to print head.
Also note, that most magnets when exposed to high temperatures will loose its magnetism,
so try to minimize contact with hot filament or print head.
Because of printed tiny hinges in upper part, I don't recommend using nozzle diameter larger than 0.4 mm and vertical resolution more than 0.15 mm. I also strongly recommend using some high quality PLA for print (Fillamentum filaments are great) as I had trouble with poorly printed hinges when I used some cheap PLA.