1. Material: silicone 2. Ability development: intellectual development, hands-on brain, grasping ability, etc. 3. The luminous model is powered by a button battery (included) 4. Develop intelligence and cultivate childrens interests 5. Durable rotation 6. Press the bubble design, not easy to deform 7. Wear-resistant and bite-resistant, durable 8. Sealed interface, waterproof and easy to clean 9. Size: 7.8x7cm 10. Weight: 60 grams