This pack of 2 Oral-B Precision Clean replacement electric toothbrush heads are compatible with the entire lineup of Oral-B electric toothbrushes, except for Oral-B sonic toothbrushes. The Oral-B Precision Clean bristles reach deep between teeth and cover more surface, leaving your whole mouth cleaner than a regular manual toothbrush whilst powering away up to 100% more plaque for a superior clean. The shape of the head allows the bristles to surround each tooth for individual cleaning and penetrates hard-to-reach areas. Oral-B toothbrush head bristles reach deep between teeth to help remove plaque. The indicator bristles fade as a sign to replace your toothbrush head for a better clean (about every 3 months) Always read the packaging.