Security door alarm area intruder alarm. With alarm switch, it can be used as a door stop alarm or door stop. The door stopper alarm in “on” status,when door pressure is applied, the door stoppers security will be triggered while make extremely loud 120 dB alarm, helps deterintrudersr and wake/alert homeowner or renter. Door stop alarm in "off" condition, door alarms for home can be used as common damping rubber door block, holding door in any open position. The weight is only 4.7 ounces, so handy to take with you when traveling or staying in alone. No installation required, door block alarm, battery-operated (requires 1x9V battery, not included), push the turn on button in the back of the door stop alarm into working status; place it behind any inner pull door. Please ensure that the gap between the bottom of the door and the floor is 0.39" (10mm) to 1.38" (35mm) before purchasing the rubber door stop. 3 Sensitivity Levels – High-Medium-Low Sensitivities, door stop with alarm, which can be adjusted to suit your individual needs. There are high, medium and low setting levels, and the pressure sensitivity can be adjusted depending on different situations. High sensitivity is recommended when the space between your door and the ground is less than 0.39 inches. Door stop alarm travel. If your floor space is between 0.39 and 1.38 inches, medium or low sensitivity is recommended. Loud alarm powered by a 9 V battery – The alarm volume can be up to 120 DB, a very loud noise that would definitely scare intruders and alert the owner. The safety door cap may better protect you and your family. The door stop alarm powered by 9V battery (Note: Battery not included). Door Stop Alarm – Weight: 4.7oz Dimensions: 5.45 x 1.8 x 1.52 inches. Door Stop Door Alarm Security Alarm, Corner Intrusion fits the internal pull door whose seam gap is 0.39" (10mm) to 1.38" (35mm). If the gap is greater than 1.38 inches, door security devices will not fit your door. Requires a 9 Volt Battery (not