R4WB4ECMB-5G 4 Channel 500GB DVR Surveillance System with 10.5-Inch Built-In Monitor and 4 600TVL Wireless Bullet Cameras (Black) Connection type: 4 RJ12 Each camera has a built in microphone for audio monitoring capability View and access live and recorded video remotely over the internet or mobile phone Hard Drive: 500 GB Resolution: 600 TV lines