Dahua NVR4104HS-P-EI Or NVR4108HS-P-EIOr NVR5216HS-16P-EI. Up to 6TB of optional hard disk space (pre-installed, if chosen). changing, audio detection, no SD card, SD card full, SD card error. Alarm: 1 in, 1 out; audio: 1 in, 1 out; supports max.
eBay