Note: In the normal condition, the family wifi signal only 15-30 meter without wall. If the WiFi signal is not good, keep the wireless router and doorbell more closer. You can also add a WiFi signal amplifier from aliexpress or local store. App's Photo and Video buttons, pictures and videos are kept on the phone and memory card. Motion Detection Alarm Video cannot be maintained in mobile phone and memory card.Only support upload to free cloud storage. set1: Simple doorbell(no wifi/video function,not include 12v23a battery)set2: Wifi video doorbell(no 2pcs*18650 battery,no 18-24V AC Power)set3: Wifi video doorbell+ Chime (no 2pcs*18650 battery,no 18-24V AC Power)set4: Wifi video doorbell+Chime+32GB TF memory Card (no 2pcs*18650 battery,no 18-24V AC Power)you can test wifi video doorbell by USB date line,2pcs*18650 battery,18-24V AC Power. Features: 1.Two 18650 specification batteries.2.Million HD pixels collocated with 166 degree wide-angle lens3.Support mobile phone remote fast wake up device within 1 second.4.2.4G Wi-Fi connection5.High quality two-way talk with noise cancellation6.Support PIR motion detection, when someone hovers at the door, immediately alerts push notifications to the mobile phone.7.Day and night mode automatic switching, whether day or night, the image is clearly visible, for your safety and family security.