Ultra-soft, elasticity is good. No need to close your eyes when washing hair. Make the shampoo a funny experience for the kids. When washing, it can prevent the clogging breathing. Comfortable and flexible for time-and-time again use. To prevent the shampoo & water touches the baby`s face. Protects your baby or toddler`s eyes from shampoo and water. When wash your baby`s hair, water will not run to the baby`s face. Kids can use when the head perimeter is more than 40 cm (High Elasticity) material: eva foam external max diameter: 28.5 cm. Internal max diameter: 13.5 cm.