... support up to 8 CH, D1 resolution video data to PC through USB 2.0 interface.System Function· Highest performance/Price ration USB2 ... .0 4-CH (4-CH Video, 4-CHAudio)realtime USB DVR BOX ... OS supportingAndroid 2.2 or above,iPhone, iPad, IOS4.1 or above realtime 8CH USB DVR,8ch video capture card,USB2.0 cctv dvr, ...