Hi Shapeways fans, A Gearus Line is a gear-matching puzzle. The object is to place the six oddly-shaped gears over the four diamond-shaped shafts such that they rotate freely. When gears are placed incorrectly, then the final gear won't fit, or the rotation will block. The number of combinations may seem huge. However, some clever thinking can reduce this number significantly. The net acceleration of the three gear pairs should be zero, as the red shaft spins at the same speed as the light-green one. So any acceleration from one or two gear pairs should be compensated by the third pair. Watch the YouTube video. Buy the puzzle at my Shapeways Shop. Read more at the Non-Twisty Puzzles Forum. Check out the photos below. Enjoy! Oskar