1,3 ports USB HUB Card reader 2,Support MS/Pro Duo,M2,SD/MMC,Micro SD 3,USB 2.0 interface card reader ... USB 2.0 Card readerHigh Speed USB2.0, Compliance with USB 1.16 card slot:1 slot: CF I ... power Supply ,No external power supply requiredSupport high speed card, Slim size ,easy for carryTransfer files between your computer ... windows 98/me/2000/xp/vista,Mac OS9.1 or higher