The Oral-B iO Ultimate Clean toothbrush head is especially designed for an effective clean for up to 100% plaque removal as of day 1. Perfect angle The Ultimate Clean refill features Oral-B's perfectly angled bristles (16°) to deliver better cleaning along the gumline. Tuft-in-tuft Longer thinner inner bristles target hard-to-reach areas. Shorter wider bristles provide thorough surface cleaning. Replace regularly Change brush head when the iO toothbrush notifies you to get back to 100% cleaning efficacy. Find the right brush for you