1、COMBINATION OF TWO PARTS: Consist of transmitter and receiver. The receiver is the indoor unit, and the transmitter is the outdoor unit. Unique mute and do not disturb mode giving users a better home experience 2、CONVENIENT AND FLEXIBLE: No wiring, bring simple and flexible installation, mainly suitable for family homes, companies, hospitals, hotels, factories and other environments 3、SUPPORT USER SETTINGS: 55 European and American ringtones are optional, users can set any music as the doorbell according to their own preferences. Users can flexibly increase or decrease receivers and transmitters according to their needs, and the pairing method is simple and easy to operate 4、POWER OFF MEMORY: After power off, the set ringtone can be locked by memory, and the set ringtone will still ring after power on 5、LONG CONTROL DISTANCE: The distance can be up to 150‑300 meters in an open and barrier free environment, long distance remote control, stable signal and no interference with each other