This is the Kumon Kumikumi Slope. I think it's a very good product for fostering imagination. ● Create an original course and roll the balls to the bottom! You can build your own course to roll the balls while combining various parts. ● By assembling the course while paying attention to whether the balls roll smoothly, you can enhance your creativity. ● It's a bestseller that both adults and children will enjoy. ● The parts include various shapes, such as sloped parts where the balls roll slowly, parts where a water wheel spins when the ball passes through, parts with points that switch the course each time the ball passes through, and dish-shaped parts where the balls spin and fall. One blue ball is missing. Please note that there is no instruction manual or box. Thank you.