Genuine Philips Sonicare rechargeable electric toothbrush head compatible with all Philips Sonicare snap-on rechargeable toothbrush handles #1 Recommended power toothbrush brand by Dental Professionals Clinically proven to reduce gum inflammation up to 100% more after 2 weeks of use Up to 7x healthier gums versus a manual toothbrush.Use with a Philips Sonicare DiamondClean Smart, Smart mode-pairing automatically selects optimal mode & intensity level, tracks your usage & notifies you when it is time to replace your brush head Replacement:Every 3 months