HD DVR -H.264 realtime network HD DVR -USB,PTZ,Audio,Network,VGA,HDMI -SATA HDD ... up to 2TB -Up to 720P resolution 4 channel HD DVR ... Features: 1. H.264 Real-time Recording, support USB, PTZ, network, two-way ... CPU; Steady System Function;4. Playback, video, network transmission, mobile browsing, and backup etc. work simultaneously ...