The push button transmitter (outdoor unit) is powered by 1pcs 12v 32a battery. indoor receiver unit is powered by 2pcs aa batteries. (battery is not included).
38 melodies and 3 levels adjustable voice volume, reminding you the coming of your guests by lovely songs.
design with led indicator, more practical and convenient.
all day long anti-interference system, avoid interferences outside or between neighbors.
simple and easy wireless installation, just plug and go; save troubles and money.