【Easy to install】Simply plug the receiver into a power outlet and then attach the transmitter to the wall or door frame using the included adhesive tape or screws. No need to worry about cables 【400 m radio range】 The penetrating wireless signal can transmit up to 400 meters in an open and accessible space, even if you are several rooms away or on a different floor, you will not miss a visitor. Ringtones do not interfere with other devices in your home or your neighbors 【55 melodies and 5 volume levels】 Doorbell receiver, the sound is full and clear; ringtone. Entrance doorbell 【Waterproof and LED design】Made of high-quality materials, the wireless transmitter is waterproof to IP55 and the performance is stable for outdoor use. Blue LED lights on the button and receiver provide a visual cue for owners and visitors and a fun and thoughtful design for the hearing impaired. 【memory function】 The wireless doorbell set remembers the last melody and volume after switching off; no reset