Explore N' Grow Busy Gears has been adapted to accept a standard 3.5mm switch (sold separately). Press your switch or the button on the toy itself for fun lights, movement, music and giggles. This is a perfect toy to encourage peer interaction, enhance visual and sensory skills, teach colors and prepositions, and teach cause and effect. Gears can be moved and stacked. An automatic "shut-off" helps conserve battery life and a convenient carry handle makes it easy to take on the go. 3 AA batteries included. Measures approximately 2.6 x 14.5 x 10.5 inches.