Hard disk drive is not included in this 16 channel DVR. Option to install an internal surveillance hard drive for continuous local recording. Supports 2 internal surveillance hard drive of up to 16TB each. Compatible with WD Purple, Toshiba and Seagate surveillance hard drives. External hard drives are not suitable for use with TIGERSECU systems. This TIGERSECU Super HD hybrid security DVR is a full featured hybrid digital video recording system designed for use with 2MP (1080p) HD TVI, AHD, CVI, and analog security cameras. For optimal performance, use this TIGERSECU DVR with TIGERSECU security cameras. Remotely access and play surveillance footage and control the security DVR with no contract or monthly fees with TIGERSECU's HD Viewer. For optimal performance, 1 Mbps upload speed is recommended for each 1080P camera. Bitrate settings can be adjusted in the DVR to accommodate slower network speeds. Mobile app requires iOS 9.3 or later and Android 9 or later. Compatibl