Areox 2-In-1 Wireless Entry Doorbell Door Chime (White) Press the buttion on the side of the door bell to change songs 38 music tunes for you to choose, can change the voice on 3 level Press the remote control button to trigger the wireless receiver doorbell to chime No obstruction wirless working distance up to 100 meters and up to 20 meters while obstructions exist Double side stickers on the back of the remote control button and installation holes back of the doorbell, very easy to install