Oral-b Trizone Toothbrush Heads Replacement Refills For Electric, 4 Count (Pack of 1)Promotes cleaner teeth and healthier gums vs. a regular manual toothbrush Features triple zone cleaning with three bristle zones to deep clean in hard to reach areas Helps you brush as you would with a manual toothbrush for easy handling Indicator bristles fade as a sign to replace your toothbrush head for a better clean (about every 3 months) Compatible with the entire line up of Oral B electric toothbrushes, except for Oral B sonic toothbrushes