CACAZI FA99 Wireless Doorbell Kit Home Door Bell 36 Melodies Alarm 4 Adjustable Volume Levels (EU Plug),1 Receiver and 2 Transmitter - Silver ?Working together with the transmitter. Just press the button and the doorbell will receive a signal,you immediately know that someone is coming ?Higher penetration without worrying about signal obstruction ensures you will never miss a visitor,even if you are a few rooms away or on another floor ?Easy to Install. Just plug the receiver into a socket,and mount the doorbell transmitter on the wall or anywhere you want,the effortless installation ?Features 36 melodies and 4 level adjustable volume. It meets your different needs. Setting different ringtones for different receivers can let you know which door the visitor is at ?Dustproof and waterproof,suitable for any home,townhouse,apartment,office,school,hospital,hotel,etc Specification: ?Music alarm: 36 music optional ?Volume: 4 levels of volume adjustable (can be adjusted to silent mode) ?Transmitter power supply: no battery required ?Receiver power supply: plug in the power supply (110V-220V) ?Transmitter size: 70*46*24mm ?Receiver size: 91*59*25mm ?Remote control distance: 150m (straight-line distance without obstacles) Package included: ?1 x Receiver ?2 x Transmitter ?1 x English User Manual ?1 x Installation Tool Kit ?Other things not included