Grimm's Mosaic Rainbow | Large 100 PiecesThe elemental cubic form of these blocks inspires children to build simple walls, foundations, fences, stalls as well as houses, towers and castles. The basic shape is also very useful for making tables and stools. By building and playing with these blocks, children develop fine motor skills and spatial thinking skills. 100 building blocks in a wooden frame. Materials: lime wood, non toxic water based color stain non toxic plant based oil finish.