Gravitrax Starter Kit - Experience the Power of Gravity GraviTrax is an innovative marble run and stem toy for boys and girls made with high quality components, designed for ages 8 and up. It comes with 122 pieces and is an ideal holiday or birthday gift for smart, curious kids aged 8 and up. Innovative - the GraviTrax interactive track system allows you to design and build your own race tracks and experiment with gravity, magnetism, and kinetics to propel your ball to the finish.
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