36 Music Tune Melody 2 Remote Button + 1 Wireless Doorbell Door Bell Receiver The special and pleasant sound of the doorbell has several bel cantos for all people to choose. Up-dated intelligent flash light design brings convenience to the hearing handicapped. No wiring or drilling, wireless transmission to master the item. the battery inside the button can last for one year(20 presses per day).The batteries Not included Simple vivid installation design