Alarm sound when the thief pushes open the door or window Low price and , easy to install and use Scope of use: doors and in a wide range of places such as homes, shops, factories, warehouses, etc. The product is small and exquisite, easy to install, and the double-sided adhesive tape provided is easy to install on the door or window. It is a cheap, high-quality, economical and practical technical precaution. Simply paste the main and auxiliary parts on the door and door frame, or on the two , and align them (leaving a space of about 5 mm). Once the thief prys the door, prys the window, attempts to steal (the main and auxiliary parts are separated), the alarm can emit a strong siren, deterring the thief, reminding the owner and the people around to catch the thief. When you want to open the door or window, you can control it by the switch. It is suitable for anti-theft of residential houses, offices, store counters, etc. Power supply: 2 batteries of size 7 (not included in this unit, need to be prepared by the customer) Alarm sound: 90 dB installation method: 1. Use double-sided tape to fix the host to the door/window, 2. Glue another bar magnet to the door frame in a straight line along the prompt line of the host. 3. When checking the settings, set the host switch to the "ON" position. 4. Open the door and see if the siren sounds. Colour:White Material:ABS Package Contents: 4 x Alarm Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.