Electric Movement Rechargeable Electric ToothbrushThe S520 oral care system includes a rechargeable toothbrush designed with sonic wave technology that provides 40,000 sonic strokes per minute to effectively remove plaque without irritating your gums. It's ideal for those hard to reach areas and removes even the toughest stains to leave your teeth naturally whiter! It comes with a 2 minute timer with a 30 second vibrate alert in order to remind you to brush a different quadrant of your mouth, The 4