Products for sound sleep reminders alerts the user to wear the head tilted forward ear. Role is safe to drive correct posture preventing myopia but also more suitable for students. Keeps drivers awake! Prevent from fall asleep. Nodding off at the wheel can put you and other drivers at risk for an accident. For divers safety non sleep is the best choice. Usage directions: 1. Wear it on the right ear properly as illustrated. 2. Turn on the switch 3.Examine whether it is in normal operation: it beeps or vibration when you are leaning your head forward and makes no sound while sitting straight it is at normal stare. 4. Please turn off the switch and put it away when you do not use it. 5. Keep it away from high temperature and damp.