product description1.USB rechargeable battery: The personal alarm is made of rechargeable lithium battery, not a button battery. No need to replace the battery, use the usb data cable to charge directly, the charging time only takes 30 minutes, and the standby time is 1 year. 2.130 decibel safety emergency alarm: When you are in danger, it can make a screeching sound to attract attention even from 300 yards away. Up to 50 minutes of continuous sound to ensure emergency use. It will replace self-defense weapons to keep you safe, like pepper spray3.2 How to use Pull out the contact pin or quickly press the switch twice to trigger the alarm4. LED emergency flashlight: The bulb is bigger and brighter than the flashlight of traditional security alarm5. Lightweight and Portable Alarm Keychain: The Self Defense Alarm can be attached to purses, backpacks, keys, belt loops and suitcases. It can also be taken on the plane, very convenient, suitable for students, joggers, elderly, children, women, night shift workers. *In order to ensure the normal work of the product, please check the quality of the product regularly and charge it in time.