The document describes the specifications of 4/8/16 channel H.264 DVR security systems. Key details include support for real-time recording of up to 16 channels of CIF video and playback of 16 channels simultaneously. The DVRs also support built-in DDNS, mobile surveillance via 5 operating systems, powerful central management software, and simultaneous network viewing by 16 users. Storage options include support for 2 x 2000GB HDDs on the 16-channel model.