Compatible With Universal Serial Bus Specification ver2.0 And Also Backward Compatible With USB1.1,USB 2.0 transfer rate up to 480Mbps ,backward USB 1.1 transfer up to 12Mbps Data copying between cards without storage intermediate,and it also allows you to upload photos/data from compatible media cards to a computer抯 hard driver Four card slots in-use one active LED It is compatible with WinME,Windows 2000 and Windows XP,Windows Vista operating system,it is also compatible with Mac OS 9.2 or higher operating system, Metal Frame for 3.5"" drive bay "