Easy to wear, just hook it over your ears! Simply hook it over your ears, and when your head nods due to drowsiness, the angle detection device activates. It emits a sharp warning sound, waking you up with a start. The sensitivity of the device to the nodding motion can be adjusted with a dial. You can switch between alarm sound and vibration modes. ● Battery: AGS x 1 (included) ※ This product is an alarm aid and does not guarantee safety. ■ Material: ABS resin ■ Size (approx.): 5.5 x 5.2 x 1cm ■ Weight (approx.): 7g ■ Color: ・ Black ■ Made in China