HIGH BRISTLE DENSITY: Oral-B Gentle Care Replacement Brush Heads are densely packed with up to 4000 soft bristles for a gentle and perfect clean COLOR-CHANGING BRISTLES: The Oral-B replacement brush heads feature color-changing bristles to signal when to change the brush head to maximise your clean REPLACE EVERY 3 MONTHS: A worn-out brush head makes cleaning difficult, leaving bacterial plaque behind. For a superior clean, replace your brush head when the bristles fade to white EXCLUSIVE FOR ORAL-B iO HANDLES: Get superior cleaning power with the only brush head designed exclusively for – and guaranteed to fit – your Oral-B iO electric toothbrush TRUSTED BY DENTISTS: Oral-B is the #1 Dentist-Recommended Toothbrush Brand Worldwide