... -Audio,Alarm,VGA,USB,remote control,internet Surveillance system 4CH H.264 Stand alone network DVR Features: 1.Second-generation video compression ... at the same time support the operation of recording, playback, network transmission, backup, mobile control and interface operation 3.Two USB ... usage: 4CH H.264 CCTV DVR Stand alone with external network access surveillance system 4CH H.264 Stand alone ...