Radius Intelligent Replaceable Head Toothbrush is the first toothbrush in the world to have radial bristling which makes brushing easier and more effective. Each toothbrush comes with a 2 minute timer that beeps once and the green light flashes once every 30 seconds until 2 minutes is reached. The light changes to red to indicate time to check bristle wear after 180 uses. Depressing the button resets the meter to zero. Replaceable heads reduces environmental impact.