Get closer to the Quadrilla action with three gutters that make your marbles race around the outside of the colored blocks on their way to the bottom.Looks cool and extends run-time.Praised by the Wall Street Journal as one of the top toys to teach kids code and STEM principles. German Engineering Design Inspired by Da Vinci circles with Endless Creative Building Possibilites for Spatial Thinking Minds. Age reccomendation 4+