digital video recorder dvr -H.264,4chs video,1ch audio -3G Mobile view -Factory Price ... ,snapshot & FTPAudioAudio CompressionG711ABidrectional TalkSupportRecord &PlaybackRecording ModeManual>Alarm>Video Detection>ContinuousPlaybackMulti channels playback simultaneously,pause,stop,rewind,fast ... to second)Storage &BackupSpace OccupationAudio 28.8MB/H ;Video 25~450 MB/HRecord StorageLocal Hard disk and ...