The FirmTek ThunderTek/PX2+2 supports up to two Mac OS X bootable high-speed 6-Gig 2.5" SSD or HDDs directly on the card inside the expansion chassis and two external eSATA ports for connecting existing devices over Thunderbolt™. The ThunderTek/PX2+2 supports both direct-connect and port-multiplier eSATA enclosures. Support up to 12 Drives per ThunderTek/PX2+2 when used with dual SeriTek/5PM enclosures and dual internal 2.5" SSD or HDD. This new product is designed for use with the 2011 or later MacBook Pro, MacBook Air, iMac, Mac mini plus the late 2013 Mac Pro and other Thunderbolt™ equipped computers. Mac OS X 10.9 "Mavericks" is supported as well as Mac OS X 10.8, 10.7, 10.6.8, BootCamp and Windows 7 & 8.