Features: 1. How It Works - No alarm sound will be issued when the closing distance between the main unit and the magnetic strip is within 1cm. When someone illegally opens the door and window (the alarm is separated from the magnetic strip), the alarm immediately emits a sharp alarm sound. 2. Low battery intelligent detection. When the battery voltage is as low as 2.1V, the warning alarm will make a "beep" sound to remind you to replace the battery. 3. Multi-scheme collocation, one warning alarm can be equipped with up to 20 remote controls for home use; one remote control can be connected to up to 50 warning alarms. 4. Easy installation, multi-mode application, fast and convenient. Equipped with double-sided tape for installation, you can complete the installation with just peel and stick. 5. Perfect for home, garage, apartment, dorm room, mobile home, RV, office and more. Notice: Actual color may be slightly different from the image due to different monitor and light effect. Please allow 1-3cm deviation due to manual measurement. Description: Size: As the picture shown Sound pressure: about 130dB Ambient humidity:<90% Working humidity: -10~60 degrees Celsius Alarm battery: included Remote control distance: 15m (open space) Remote control battery: included Induction range: 15mm (no magnetic interference) Alarm weight: 60g (with battery) Remote control weight: 15g Transmission frequency: 433.92MHZ Color/Style: As the picture shown includes: 1 set of Door Safety Alarm