The Oral-B iO Series Gentle Care Replacement Brush Heads combine powerful but gentle micro-vibrations with our unique dentist-inspired round brush head design for a professional clean feeling every day. Designed exclusively for Oral-B iO electric toothbrush handles the Gentle Care brush heads help remove up to 100% more plaque than a regular manual toothbrush leaving teeth feeling clean and bright. The Gentle Care brush head combines 4000 soft bristles and a cushioning outer ring to precisely adapt to the curvature of teeth and protect gums. Since dentists recommend changing your toothbrush head every 3 months for best results Oral-B replacement brush heads feature color-changing bristles that signal when it's time for a change. Enjoy superior cleaning power with the only refill brush heads designed exclusively for - and guaranteed to fit - your Oral-B iO electric toothbrush.