Sejoy always works hard to offer users the highest level of quality and care. 40,000 micro-brushes per minute, this black electric toothbrush gives you a thorough cleaning while making reduced noise. 5 personalized modes not only take care of your various demands.Equipped with a 2-minute smart timer, it will automatically shut down after two minutes, and intelligently pause every 30 seconds to remind you to change the brushing area. IPX7 waterproof, you can enjoy brushing your teeth in the bath or shower. Each brush head lasts 3 months so 8 will last for about two year. If the rechargeable toothbrush bristles fade in color, it's time to replace the brush head.