Meffert Puzzles Gear Ball puzzle is the latest addition to a line of gear puzzles created by Oskar van Deventer, a world-leader in the development of logic puzzles. This head-spinning, amazingly constructed puzzle develops logic, spatial reasoning and strategy skills while serving as a brilliant piece of art. You receive great value from this puzzle that can be enjoyed for hours, with each attempt to solve it offering you a new and rewarding challenge. To play, simply hold the gear ball with both hands and then twist it in opposite directions. When the gears move, the colors on each of the 6 sides change â€“ including the back frame â€“ and youâ€™re in charge of configuring it so that a solid color frames each side. Uwe Meffert started designing rotational puzzles in 1976 with the invention of the Pyraminx. Since then, he has created over 100 styles of rotational puzzles that are distributed worldwide. Use is a leading designer in the puzzle community and delights in finding intriguing new ways to puzzle his fans. Focus your IQ and have fun working your way through this remarkably well-built masterpiece. The Gear Ball puzzle measures 3.4 in x 3.4 in x 3.4 in / 8.5 cm x 8.5 cm x 8.5 cm. Developed by one of the World’s leading puzzle inventors, the Meffert Puzzles create a challenge that will leave your head spinning. There are 5 styles of this unique series. Collect them all. The Gear ball puzzle is a six sided sphere of interlocking gears and requires you to get a solid color on each side to solve.