Latest RF Push & Battery-Free TechnologyThis wireless doorbell is self-powered, no wires or batteries required, environmental protection and save your money. When the transmitter is pressed, it generates electrical current and sends a stable signal to the receiver. Never worry about damaging your wall or doorbell again when changing batteries! 38 Ringtones & 4 Volume LevelsOur wireless stereo doorbell speaker provides rich and clear sound. It offers a wide range of 38 ringtones and 4 volume levels (including mute) to suit your personal taste. Long press the volume button to return to the first ringtone (Dingdong). With memory function, the wireless doorbell remembers your last setting after a power outage. No Crossing or False AlarmThis small wireless doorbell has strong penetrating force and anti-interference. The range for multiple obstacles is up to 152 m (500 ft) and in open areas up to 305 m (1000 ft). It does not affect other devices in your house or the neighbors and ensures that you will never miss a visitor, even if you are a few rooms away or on another floor. Easy Installation Simply connect with Just plug in a mini receiver and attach the transmitter to a wall with the included hardware, including 2 screws and a piece of tape. Our doorbells can be used for home, apartment, school, cottages, office and more. This battery-free wireless doorbell also makes a great Christmas, birthday or anniversary gift for any home or business owner.