2) 23A 12V battery(included);
3) Pull the metal pin to activate alarm;                                                           

4) 120 Decibel Alarm Can Be Heard Up To 50 Meters Away;                                            

5) Built-In Light for Added Safety; Built in flashlight by pressing a button to turn and to turn off.                                            
6) Can be attached to the wrist and your bag/luggage, or used in the home on the door handle and a fixed fitting.
7) Suitable for joggers, elderly, disabled, night shift workers, alone people.