Features: Secure any window or door, with this small but effective security window or door alarm. 110db sounds level alarm, it is loud enough to scare any prospecting burglar into thinking twice about hitting your house or business. Magnetic sensor switch detects entry protecting your home or office whether you are in or out. Powered by 3 * button cell(excluded), low power consumption, energy saving. Small size, easy to use, no external power supply required. Easily mounted by adhesive tape to Window or door. It is suitable for theft prevention of residential houses, offices, store counters, etc. Specification: Condition: 100% Brand News Material: ABS Color: As picture shown Alarm Level: 110db Battery: 3 * AG13 button cell (Not Included) Installation: 1. Use the double side adhesive tape to fix the main unit at the side of the door / window. 2. Attach the bar magnet to door frame / window frame with the arrow aligning with the reference line of the main unit. 3. Test the setup by switching the system to "ON" position of the main unit 4. See whether the alarm can be triggered by opening the door / window. Package List: 1 * Transmitter 1 * Door Magnet 1、Secure any window or door, with this small but effective security window or door alarm. 2、110db sounds level alarm, it is loud enough to scare any prospecting burglar into thinking twice about hitting your house or business. 3、Magnetic sensor switch detects entry protecting your home or office whether you are in or out. 4、Small size, easy to use, no external power supply required.Easily mounted by adhesive tape to Window or door. 5、It is suitable for theft prevention of residential houses, offices, store counters, etc.