1. Highly efficient sonic frequency 2.Waterproof IPX7 and non-slip design 3.Changeable brush head and battery 4.Slim design, easy to hold Package:1 x toothbrush with 2 interchangeable heads (Battery Not Include) How to open the package The left hand is holding the bar code direction, and the right hand is crossed from the right side. How to replacement brush head Rotate brush head to the right and pull up How to install Battery Rotate base to the left, remove the base, insert battery, put the base back on by rotating to the right. How do you use it When brushing teeth, move the brush head back and forth from central incisor to back teeth. Be careful not to exert too much force. Once toothpaste is bubbling, turn on sonic toothbrush and continue to move the brush head back and forth from the central incisor to the back teeth. Brush each quadrant of teeth for about 30 seconds. Cleaning YTSs sonic toothbrush is easy and more convenient that traditional toothbrushes. After brushing is complete, place the brush head under water and turn on the toothbrush. aGently tap the brush head to remove residue and remaining toothpaste from the brush head. Alternate brush heads to allow additional time for brush heads to dry. This will help keep your brush heads clean which is important for people with gingivitis and periodontitis. In addition, alternating brush heads will extend the life of the bristles.