MonkeyJack 2PCS Practical Door Knob Handle Alarm Door Alarm Burglar Alarm for Home Dorm Travelling H

ust hang the alarm in door handle/knob, when there is someone opens the door or touches the door handle from either side, the alarm will generate loud alarm sound to inform there is a intruder.<br>Work as an anti-theft alarm, alarm siren up to 120dB.<br>Easy to use and installation, no wiring needed (requires 3xAAA batteries, not included); just simply hang the alarm on the inside of your door handle.<br>Perfect travel alarm and great for home, hotel, dorm, etc.<br>The sensitivity may be affected by the composition of the door handle