Of discrete and comfortable design, Nap-Zapper anti-sleep slips behind the ear and alerts you as soon as your head leans beyond certain pre-established angle.

1. Take the small auricle in your hands,
2. Look to the back a small button is there, activate it,
3. A ringing will be made hear,
4. To wait until this one stop,
5. Then, place the auricle on the ear and lean your head,
6. You should hear alarm when your head leans of more than 15 degrees.