1) SAFETY: All pieces are non toxic made with high quality ABS plastic. No rust， not to hurt the hand 2) BUILD ENDLESS COMBINATIONS: Create A variety of forms. Use your own imagination，let your baby become a little inventor! 3) LEARN WHILE PLAYING: Helps children build fine motor skills， hand and eye coordination and generate ideas and creativity 4) SOCIAL DEVELOPMENT: Encourages children to work together to build creations. Great family bonding activity will have 5) FIRM AND STABLE.3D construction， using fasteners to assemble different parts， build and connect three-dimensional model with the nut， parts and components connect firmly， not easily scattered， exquisitely and vivid， full of fun