【4K 8 Ports NVR Upgrade 16CH Expandable】This 4K 8-port NVR can expand up to 8 PoE cameras. If you additional purchase a PoE switch (not included), you can update to 16 channel system. It provides you with the flexibility to expand additional cameras. You can add more (ZOSI only) 8MP, 5MP or 2MP POE bullet heads or dome cameras. 【Motion Detection & Sound Light Alarm】With the advanced PIR Motion Detection technology, you will receive instant App push notifications when motion events are detected. And this camera stays alert with the smart light and sound alarm system that reacts in time to any potential danger triggered by human motion events. Built-in brilliant white lights and high-pitched siren offering double insurance and let you stay protected even when you are asleep. 【Two Way Audio & Remote Access】Built-in mic and speaker let you stay in touch with your household. And you can live view & playback on mobile phone anywhere anytime. 【Stable Plug and Play PoE System】Simple PoE connection makes it easier to set up and install your home security camera system. The digital signal will keep a real 8mp high-definition image via ethernet cables. 【24/7 Recording & Live View Share】Built-in 2TB Security Grade Hard Drive, users are provided reliable 24/7 recording.Support long continuous recording and backup.NVR can be set to automatically overwrite the oldest internally stored footage or you can transfer those video files by USB to a memory stick or external Hard Drive. And it supports remote access, live view and playback by multiple family members.