INNOVATIVE TECHNOLOGY: The Y-Brush adult replacement brush easily adapts easily adapts to your mouth shape for an optimal brushing, fitting a wide range of Philips Sonicare handles. Its 35,000 nylon filaments bristles ensure a more efficient clean than standard brushing. FEATURES: A highly flexible "Y" shaped brush made of nylon bristles angled at 45° to remove plaque from between your teeth and also care for your gums. Validated by in vitro and in vivo tests. PROVEN EFFECTIVENESS: Designed with health professionals, numerous efficacy tests show that Y-Brush removes plaque just as effectively as a standard sonic toothbrush -- in less time. Discover the Y-Brush way to enjoy clean, healthy teeth and a bright smile! REPLACEMENT BRUSH: The brush should be replaced every 6 months. Its 35,000 nylon bristles remove dental plaque from all teeth simultaneously. Designed for adults and individuals ages 12+. COMPATIBILITY INFORMATION: This product is NOT COMPATIBLE with Y-Brush handles (NylonStart, NylonKids, NylonBlack...) and NOT COMPATIBLE with Sonicare Essence, Essence+, 4100, SonicareOne, HealthyWhite, HealthyWhite +, Flexcare, Flexcare+, 2 Series Plaque Control, 3 Series Gum Health, DiamondClean, Flexcare Platinum, or PowerUp Battery models. Compatible with Philips Sonicare models - Y-Brush Replacement Brush Head - Flexible - One-stroke Technology - Renewable Every 4 Months - Adults