DURABLE: In case of those accidental water drops, the IPX7 waterproof certified design allows KidzSonic to be submerged in 3 feet of water for up to 20 mins. GROWS WITH YOUR CHILD: From toddler-hood through preschool, KidzSonic’s affordable bi-level DeepClean replaceable brush heads come in 3-6 yrs and 6+ yrs sizes. (1x 6+ yrs brush heads & AAA battery included). FORM GOOD HABITS: Award-winning design made for small hands, with a simple ON/OFF button, make it easy for your little one to brush on their own while the smart 2 min disco light timer with 30-sec quadrant change pulses teaches your child good brushing habits. GENTLE & EFFECTIVE CLEANING: The age-appropriate sonic vibrations and BPA Free DeepClean Flossing bristles, designed for smallmouths, clean interdental, and gingival regions free of harmful plaque with a 21% increase in reduction over manual brushing. FUN DISCO BRUSHING: Flashing disco lights turn the fight-to-brush to a want-to-brush as alternating colors light up the brush head to create an entertaining and fun brushing experience.