3D puzzle is unique design of an interlocking 3D wooden brain teaser.

Step 1: Assemble the 6 scraps of balsa wood into the curved structure, using the 3 needles as columns

Step 2: Place the 5 plexi-glass rings on the far left needle in size order (the larger radius on the bottom, the smaller on top)

Step 3: Try moving all the rings to the far right needle, in size order, making sure you move one ring at a time, and a smaller ring is always on top of a larger ring