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Triple Play 4-Bar Link Maker Kit
Build a model of four-bar linkage! Use the hand crank or attach a motor (sold separately) to watch the marbles ascend and then flip-flop down again! It's part of the first Marbleocity marble machine line to feature colorful plastic accents! Perfect for beginners; one hour build time. Triple Play models can connect to one another for bigger fun! Also works with Marbleocity Motor Kit, sold separately. For ages 9 and up.