Self Defense Alarm 120dB Anti-wolf Girl Child Women Security Protect Alert Personal Safety Scream Loud Self Defense Products

It is used to detect whether the plug is inserted in the alarm or not.
When the latch of the alarm is unplugged, it will immediately alarm, Alert the user that there is an emergency; 
You also can take it with you. When there is an emergency, unplug the alarm latch immediately, the sound will scared or remind around person, Re-insert the latch of the alarm. It will stop alarm.