This door knob alarm is a dual purpose 120db alarm. It acts as a both a burglar alarm and a personal alarm. Carry it with you and just pull out the metal chain to sound the alarm and deter an assailant. Hang it on any metal door knob and it instantly and automatically sounds when an intruder touches the door knob.
The 2-in-1 door knob alarm may be placed in hand, pocket, or handbag with the attached metal chain wrapped around the wrist so that if the user is being attacked, or the handbag snatched, the metal chain is pulled out and the alarm is activated. The loud piercing siren will continue sounding until the metal chain is plugged back in. Uses one 9-volt battery (not included).