Difficult maze-type puzzle...Put the little (1/4 inch) steel ball in one hole and try to guide it out the other hole. It helps to tape over the entry hole. . Do NOT print the "pathway" file. It is to be a helpful guide; the dotted lines show the dead-ends. . No supports required to print. Ensure both pieces are properly aligned before gluing. If you wish to be cautious, tape the pieces together instead. . It will take a deft touch to solve; I'm still working on it...no luck yet. . Designed with TinkerCad.