Baby Gym. Music plays. Movable toys on the overhead gym encourage baby to bat and grasp. Move the arch down for tummy-time play, Lights sparkle. And that's just the beginning or let baby sit and entertain you with a Techhark piano concert! Requires 3 AA batteries. Develop & Grow: Piano keys Strengthen motor skills as baby gym stretches & kicks Colorful linking toys Enhance eye-hand coordination as baby grasps & bats Responds to baby's touch Musical Baby Gym rewards help baby understand the magic of cause & effect Dancing lights & mirror Stimulate baby's visual sense & promote self-awareness.