Designed for developing kid’s cognitive ability. Made of high quality wood, non-toxic paints and sturdy wooden construction. Lightweight and harmless. The colors are relatively bright, and a variety of learning modules are combined to start the children's learning journey and increase the children's attention and interest. Puzzle from material to finished product, there are 108 processes to ensure the block free of sharp edges and corners. For the safety of children, all corners are processed with rounded corners. Environmental Water-based paint doesn't contain organic solvents material. It doesn't have irritating odor, harmless to human body, doesn't pollute the environment.