Dear respected buyers, if there is damage to the item or it is not functioning properly, please notify the seller first in the chat, and don't rush to make a bad assessment or give 1 star, because that will be very detrimental to the seller. Features: Hearing training, you can exercise your baby to perceive external sounds and arouse the brain. Explore cognition, let children learn knowledge through play, and experience different learning way Body kinematics, let the child's eyes and hands move, and get through hands-on ability Puzzle enlightenment is the best good thing to enlighten children, attract children to play and think Cooperative interaction, you can play with other friends, and create a range of mutual learning. The battery is not included.