... Network, Alarm; -Phone surveillance,CMS, Audio; -Dual stream technology 4 Channel DVR Recorder H.264 H.264 compression, high definition4CH ... so on, total 26 languages supported.4 CH playback,4 CH audio & video synchronization.Video BNC 4 input 1 output,Audio RCA1 input 1 ... so on, total 26 languages supported.4 CH playback,4 CH audio & video synchronization.Video BNC 4 input 1 output,Audio RCA1 input 1 ...