Wireless Door Magnet 60 ringtones/5 levels of volume /LED indicator. When , , and cabinets are opened, the receiver ring immediately. Receiver notifies when doors and are open. Whole House Security System Keep your children safe Alarm when child opens door. Ergency Alerts Preventing Break-ins. Free collocation and free combination Meet different needs and multiple combination modes. Distinguish Between Front And Back Doors All receivers sound regardless of which door is open,but each door has a different tone so you know where your guests are. If you want the sensors and receivers to work one-to-one, try the steps in "How to clear the frequencies and repair". Suitable For More Scenarios: Window,Store,Hotel,Home,office,Pet door Concern for the safety of children Caring for the Safety of the Elderly Caring for the Safety of family members Product name:Door Sensor Chime Music: 60 music Product Model:Split Sensor volume:5 levels of volume Door magnet size:64mm x 39mm x 14.5mm Receiver size: 56mm x 56mm x 20mm Door magnet sensor: use 12V23A battery Receiver: plug-in use (AC 100-240V) Remote control distance: 300 meters in a straight line on theopen ground (data from the factory laboratory) Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on Voltage:AC220V Color: Black Material: plastic Package Contents: 1 * Doorbell 1 * Receiver 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.