4ch D1 standalone DVR/ Economical Standalone DVR 5504S
4ch video&1ch audio, 4ch full D1 Real time Record, 1ch D1 Real Time Playback or 4ch D1 not Real Time Playback, 3G DVR
YS-5504S 4ch D1 DVR
4ch video&1ch audio4ch full D1 Real time Record1ch D1 Real Time Playback or 4ch D1 not Real Time Playback VGA/CVBS double out, network, USB mouse, RS485
3G Mobile Surveillance, bring DDNS, outstanding CMS
4ch D1 standalone DVR/ Economical Standalone DVR 5504S