Firefly Transformers Light & Sound Effect Tooth Brush

Kids light and sound with sound effects and flashing light for 1 min and built in Stand.How to use?Kids should brush the top row of the teeth until the light stops flashing. Repeat for bottom row of teeth .Brush twice per day. Batteries included (non-replaceable).When light longer flashes its time to change your brush. (approx 3 months).