UGEARS 3D Puzzle Mechanical Aquarium – Creative 3D Wooden Puzzles for Adults Driven by a Spring – Aquarium Wood Model…

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Underwater adventure: The mechanical aquarium is an ingenious mechanical model building kit of a saltwater fishbowl with two pet tropical fish chasing each other around in a forest of macroalgae fronds that shelter a tiny seahorse
Unique mechanical action: Up to now, UGEARS 3D puzzles for kids and adults have been propelled by rubber band motors. This aquarium engineering kit opens a new chapter: engineering toys driven by a spring-loaded mechanism