This puzzle is made of sturdy and soft wood materials that have soft edges and adequate size that is ideal for small hands to handle and play. Not only kids learn about numbers but it also helps kids develop fine motor skills, creativity, imagination, curiosity and discovery skills. This wooden puzzle set assists children in developing important skills such as hand-eye coordination, fine motor skill, basic cognitive skill. Made from non toxic material. Easy to grasp the number puzzle and fit it in tray. A perfect product for help kids learn about numbers.