MaBoRun Mini

Many styles to choose from- get a MaBoRun here: 

From eBay: BUY NOW: MaBoRun Mini

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From Amazon: BUY NOW MaBoRun Marble Run 

MaBoRun Mini IV: rolling marbles doing tricks as potential energy of gravity is converted to kinetic energy. In this mini-marble run a battery powered auger conveyor (Archimedes' Screw) brings the marbles back to the top and conservation of angular momentum produces a simulation of decaying orbits as the marbles whirl down the the main funnel shaped feature.