Features: *Wireless smart voice doorbell, talk with visitor via two-way voice intercom, which lets you know who visits your home and talk to them and let them know I\'m coming, please wait. *1 receiver and 1 push button, talk between receiver and push button via wireless connection within a large range (outdoor bell: 200m, indoor bell: 5-50m without any obstacle), stable transmission signal to make voice clear. *Receiver support rechargeable battery, transmitter supports 3*alkaline battery last up to Approach 4 months (transmitter 3*alkaline batteries are not included). *It\'s widely used for office and house, get know who is outside, and convenient for the elder who needs much more time to open the door, very practical. With 15 different ring tones and 3 levels adjustable volume. *Easy to install and use, visitor presses the outside doorbell, after getting ring, you should press the button one time on receiver to get connected and then hold to speak, release it after finishing.