The Keychain Alarm with Light combines the two best deterrents against attack…a 130db alarm and a flashing light. The alarm is activated when the pin attached to the keychain is pulled. Or by pressing the alarm button on the top of the unit. Can be used as a flashlight without activating the alarm to provide additional night time safety. Two AAA batteries included. Dimensions: 2 3/4" x 1 3/4" x 1"