Frenetically fun and addictive - that's how you could describe the foam 3D puzzles called Happy Cube® (Happy Cube). Exercise your brain and dive into the amazing world of Happy Cube with various difficulty levels. Organize tournaments with friends or family and have a great time! Assembling the Happy Cube 3D puzzle will test your brain cells, improve concentration, develop spatial thinking, coordination, and reduce stress. The basic task is to assemble a perfect cube from six pieces of the same color. It's not as simple as it seems at first glance. There is usually only one way to assemble the cube. The next task is to fit the individual pieces of the Happy Cube back into the two-dimensional frame they were delivered in. The third task and a real challenge is to create a larger and more complex three-dimensional structure by adding other types of cubes from the same group. Some structures are more difficult than others, and examples can be found on the packaging of each Happy Cube product. Four groups of 3D puzzle cubes are available, each containing 6 different cubes. Each group has a unique color scheme, style, and level of difficulty. Within each group, the cubes and thus the difficulty are distinguished by colors. There are a total of 24 different cubes available. The four groups of Happy Cube cubes: Little Genius - for children aged 3 - 7 years - single color, with various icons based on difficulty (* fruits, animals, * vehicles, sports, * weather, ** nature). These are the simplest cubes. Happy Cube - from 5 to 99 years Profi Cube - from 7 to 99 years Marble Cube - from 9 to 125 years Age-specific difficulty is just indicative, adults can also enjoy fun with cubes intended for children. This ingenious yet simple idea was introduced by the Belgian inventor Dirk Laureyssens in 1986. Happy Cube cubes are made of 8mm thick EVA foam. They are delivered in a flat two-dimensional configuration, placed in a foam frame shaped like a rectangle. Machine washable at 30°. Dimensions of the assembled puzzle are approximately 4 x 4 x 4 cm.