... ,ROHS certification 3. Experience in DVR field: 4 years, 4. Warrenty : 2 years Support:Arabic,Czech,English ... ConpressionG711ABidrectional TalkSupportRecord &PlaybackRecording ModeManual>Alarm>Video Detection>ContinuousPlaybackMax 4/8 channels playback simultaneously,Pause,stop,rewind,fast ... BNC,1 VGA output,1 HDMI(optional)Audio Input4 channelAudio Output1 channelAlarm Input8 channelRelay Output1 ...