Seagate GoFlex 1 TB FireWire 800 USB 2.0 Ultra-Portable External Hard Drive for Mac - Limited Edition STBA1000101, Silver Standardized 2.5-inch form factor with a depth of 14.5mm and shorter in length than an iPhone Edition is perfect for use with your growing library. FireWire 800 or USB 2.0 plug-and-play drive Compatible with Time Machine software Upgradeable to USB 3.0 and powered eSATA Use the same drive interchangeably on both Mac and PC computers Durable soft-touch silver finish to help resist fingerprints