Bidirectional Talk : Support Record & Playback : Recording Mode : Manual> >Dynamic Detection>Timing Playback : One channel or multi-channel playback Search Mode : Time/Date ,Motion Detection & exact search(accurate to second) Storage & Backup : Space Occupation : Audio28.8MB/H Video25450MB/H Video storage : Hard disk, , and net Backup Mode : Network, mobile Hard disk and USB Interface : Video Input : 8channel, BNC, 1.0Vp-p,75 Video Output : 1 channel, BNC, 1.0Vp-p,75 and 1 VGA output Audio Input : 8 channel audio Audio Output : 1 channel ,RCA, 200-3000mV,5K Net Interface : RJ-45 (10M/100M) PTZ Control : 1 RS485 USB Interface : 2*USB Hard Disk : 2 SATA ports (max 2048G) Environmental : Power Supply : 12V/4A Power Consumption :