With four generations face gear speed (there are 20 seconds to change the position of the time to remind) the vibration frequency is 176Hz (clean hand wash is better than 11-fold) can wash the body、 you can choose 1-2 minutes automatic shutdown、 a charging display LED lights、 there reminder lamp due for replacement brush heads、 automatic gearshift function、 etc.、<br /><br />5th generation intelligent machine use、 good cleaning effect than 4 generations、 the body is relatively high on