Origin:Mainland China Features: Put it behind your right ear, Alerts when the head lower in the degrees of 15 to 20. Especially suitable for long-distance driving or night driving. ON / OFF switch. Powered by AG3 button cell batteries( included ). Driver safety alarm can help prevent accidents caused by driver's sleep when driving. It is especially suitable for long-distance driving or night driving. It is guardian angel for drivers. Easy to use and comfortable to wear for a long time Color:Black Weight :Approx 14 g Size :Approx 5.8*5.3cm Usage directions: Wear it on the right ear properly as illustrated Turn on the switch Examine whether it is in the normal operation:it beeps when you are leaning your head forward and makes no sound while sitting straight , it is at normal state Please turn off the swith and put it away when you do not use it Keep it away from High temperature and damp Package Included: 1 x Anti-sleep Alarm