Features: This door stopper alarm is a secure alarm device widely used for home, office or hotel. Small size and wedge shaped anti-skid design; it is suitable for any hinged door. It can be inserted into door gap directly, no need to install; switch on and the stopper will give out an alarm sound if the door was open. There is sensitivity controller on the side that you can select high/middle/low sensitivity. If you need it as a normal door stopper without giving out alarm sound, you can simply turn the alarm off. Specifications: Material: Stainless steel, engineering plastic Alarm Intensity: 100db Battery: 9V battery(Not included) Size: 14*4.5*4cm/5.51*1.77*1.57" Package Includes: 1 x Door Stopper Alarm Package List 1This door stopper alarm is a secure alarm device widely used for home, office or hotel 2Small size and wedge shaped anti-skid design; it is suitable for any hinged door 3It can be inserted into door gap directly, no need to install; switch on and the stopper will give out an alarm sound if the door was open 4There is sensitivity controller on the side that you can select high/middle/low sensitivity 5If you need it as a normal door stopper without giving out alarm sound, you can simply turn the alarm off