Material: rubber balls are made of 100% safe, non -toxic raw materials, without smell, soft, without skin irritation or eyes, good elasticity, high resistance and can be used for a long time. A fun toy that children and pets love! Size/quantity: The diameter of the jump balls for children is 25mm x 25mm, the set has 100 pieces, having different patterns (Note: Not suitable for minor children 3 years old, children under 3 should use under the supervision of parents) Stress relief: he is a good assistant for anxiety and ADHD patients! Exercise the coordination of the hand, eye and brain of children, develop the creativity and imagination of children.