These brush heads improve gum health in only two weeks, remove plaque and reduce gingival inflammation. They have a rubber coated head to protect your teeth and gums. They have a BrushSync technology, improving brushing performance. Made with soft bristles, they won't irritate the gums. The bristles gradually fade in colour, letting you know when you should replace the head. These brush heads are engineered with Adaptive cleaning technology, following the unique shape of your teeth and gums. This refill pack comes with two brush heads.