... 4 Channel CCTV Security Standalong DVR *H.264 real-time high compression, support dual stream network transmission Wholesale 4 Channel CCTV Security Standalong DVR , 4CH Standalone DVR , 12VDC DVR , 4CH DVR System ... , PTZ control, Playback, System setting, File download, Log informationHard Disk1 SATA port, Max 2TB HDD supported Wholesale 4 Channel CCTV Security Standalong DVR (JD-DVR7504)