Features: 1[With 120dB Security Alarm]?If the safety door is opened, the edge of the door will press down on the plate of the door stop alarm and trigger the alarm, the alarm will continue to sound at a high volume of 120dB. 2[3 Level Sensitivity Adjustable]?High, medium and low sensitivity, three levels of sensitivity can be adjusted. It depends on how far the door touches the door to stop the alarm. 3[Door Stopper]?When the door stop alarm is not in use, turn off the power switch. The alarm can be used as a door stop to prevent the door handle from hitting the wall when the hinged door is opened too far. 4[No Installation Required]?Just put it behind any door (home, hotel, etc.). Very convenient to take with you when traveling or staying indoors alone, which can effectively give you timely alerts in unfamiliar places. 5[For Your Security]?Door stop alarm keeps doors from sliding, preventing bad guys from getting in. Protector by your side. The door stopper security alarm can be used for home and travel. Package included: 1 x Door&nbspStop&nbspAlarm (Battery Not Included)