This sneaky container has a few tricks up its sleeves. First, there are the misleading dovetail joints that slide off at an angle. On top of that, some pesky marbles are causing mischief from the inside! Use a strategic simultaneous twist and slide to unlock it (or the more chaotic shake in till you make it strategy). For many, closing the box back up and locking it again is even more challenging!
This box makes a great gag to hold a gift, or a fun way to lock up some secret belongings. As the small version there is only a tiny compartment for storage. You can get the large version for a bit more space.
To assemble, print the two parts using standard print settings (maybe a few extra shells in case someone gets aggressive trying to open it). No supports required. You will need two standard 14mm (9/16") marbles, or similarly sized spheres like these ABS beads, Acrylic ones, these steel balls, brass balls, Delrin bearing balls, Polypropylene...see, they're common!
Photographed model was printed with MatterHackers Quantum PLA (Also on Amazon)