REVO America R4D2GT2GCMB-1T 4-Channel 1TB DVR Surveillance System with 10.5-Inch Built-In Monitor and 4 700TVL 100-Feet Night Vision Cameras (Black) Cameras have a built in microphone for audio monitoring capability View and access live and recorded video remotely over the internet or mobile phone LED lighting distance: max 100ft Hard Drive: 1TB Connection type: 4 RJ12 ports