With the smart, wireless Calex video doorbell you always know who is at the door, whether you are at home or not. Via the built-in full HD camera with night vision, you can always see who is moving in front of your door or ringing the doorbell. When someone rings the doorbell, you will not only receive a notification via the Calex Smart app, the included chime that you install in your home will also sound! Because the video doorbell has a speaker with two-way speech, you can easily talk to any visitor via your mobile phone. Easy to install The doorbell is completely wireless and is easy to install. You can easily install the smart doorbell via the Calex Smart App. To connect this doorbell via the app, only WiFi is required (2.4GHz), so no hub or extra link