Gear Ball _ Meffert's Official Rotational Puzzle _ Bonus Twisted Nails Puzzle Sphere-shaped twist and turn brain teaser puzzle. Objective is to return all same color to each side. Mix up all the colors by turning halves of puzzle. Sides can rotate along all three axis. Mefferts square piece must be in center to switch to a different axis rotation. Bonus: Twisted Nails Puzzle. Separate and then rejoin the 2 carpenter's metal nails. Very cool gear like movement along the surface as puzzle is turned.