Seagate FreeAgent GoFlex Desk 3 TB FireWire 800 USB 2.0 External Hard Drive for Mac STBC3000101 Compatible with Time Machine Software, It work on a 64-bit mac running Lion. Upgradeable to Thunderbolt and USB 3.0 interfaces FireWire 800 or USB 2.0 plug-and-play Use on a Mac and PC computer interchangeably without reformatting FireWire 800/USB 2.0 desktop adapter with capacity gauge display 3-year limited warranty Durable soft touch finish helps resist fingerprints Inside the Box: GoFlex Desk external drive formatted for Mac, GoFlex Desk FireWire 800/USB 2.0 adapter base with capacity gauge, 5-foot FireWire 800 cable, 5-foot USB 2.0 cable, power supply, quick start guide