The seesaw is our largest expansion component. If the marble has enough momentum, it will roll straight into the seesaw and then continue at an increasing speed. And because you can never have enough seesaws, there are two of these in this set, along with track elements, building blocks, a base plate and marbles. Due to a large amount of elements and building blocks in various shapes, colors and sizes, there are endless combination possibilities, from simple constructions to complex scaffolding, all of which give immense pleasure. Children develop in a playful way in this way. The little master builder becomes familiar with gravity and acceleration, improves their motor skills, their creativity and their logical thinking. The Hubelino block system is 100% compatible with building blocks from other manufacturers. They do not wobble, do not slip or fall over. To ensure that the marble always rolls safely into the target, we at Hubelino pay attention to good design, accuracy and quality. All Hubelino products are responsibly manufactured in Germany from high-quality ABS plastic, comply with European EN71 standards for children's toys and carry Bureau Veritas' CE mark for product safety. - 2 seesaw swaps - 19 track elements - 20 construction blocks - 2 marbles - Hubelino bricks can be used with LEGO DUPLO bricks