The Oral-B iO Series 2 is an easy-to-use electric toothbrush that combines gentle micro-vibrations with a unique, dentist-inspired round brush head – providing a professional cleaning feel every day. It is specifically designed for manual toothbrush users who want a simple transition to an electric toothbrush – featuring a sleek design, easy one-button operation, quiet operation, and a long-lasting battery that lasts up to 4 weeks on a single charge. For optimal cleaning results, the replacement brush head should be changed every 3 months.