Philips Sonicare for Kids standard sized replacement brush heads are kid sized and have rubber molding to protect children's sensitive teeth. The extra soft bristles are designed especially for small teeth and developing gums. Sonicare for Kids replacement brush heads remove significantly more plaque in hard-to-reach areas than a manual children's toothbrush. Sonicare for Kids encourages healthy brushing habits and delivers outstanding results. Brush heads snap on and off easily for easy cleaning and replacement. For best results, Dental Health Professionals recommend that brush heads are replaced every three months. A fresh brush head every three months maximizes the effectiveness of Philips Sonicare's unique sonic technology. Compatible with Sonicare for Kids rechargable electric toothbrush only.