Powered by 18650 battery or 5V power adapter. Only Admin (The 1st people connected with doorbell) can unlock the doorbell from App.Message Function; visitor can leave a 10sec voice message in the doorbell. Camera Function; when visitor press the doorbell, the App will show visitor's photo. The item "Wifi Wireless Outdoor Ring Video Intercom Door Bell Camera Phone App Battery" is in sale since Friday, October 26, 2018. This item is in the category "Computers/Tablets & Networking\Other Computers & Networking". The seller is "northernsecurityco" and is located in London. This item can be shipped worldwide.