MusicBell Portable Wireless Doorbell Chime Kit Operating at Over 900 Feet Range 52 Selectable Melodies, No Batteries Required for Receiver (1 Push Remote Button and 1 Door Chime) &ndash; Black / White MELODIES | A Variety of Stereophonic Chimes to Choose From DURABILITY | Built For Resilient Environments, IP 44 Waterproof Transmitter REGULATE | 4 Level Adjustable Volume INSTALLATION | Easily Install and Use, Plug-In To Wall Receiver and Mount To Wall Transmitter COMPATIBILITY | Conveniently pair additional transmitters or receivers.