Building and constructing with Mobilo promotes social skills, fine motor skills, creativity, perseverance, and three-dimensional thinking in a playful way. This set of gemoetric pieces is compatible with all mobilo and is the perfect addition to your existing collection, allowing more children to play and create! 26 pieces including 4 cubes, 8 rectangles, 4 squares, 4 angles and 6 triangles. 3yrs+.