Fat Brain Toys
Each set is made up of hollow stacking cubes and a variety of perfectly flat tracks. The paths cut out of each track widen almost imperceptibly from one end to the other, creating an invisible slope that propels the marbles forward. Watching them go is like magic in slow-mo! Explore more with the 73-piece Builder set with four guided builds. Or, collect them all, combine them, and turn your Trestle Tracks into a Trestle Metropolis!
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