Seagate's 500GB GoFlex Pro for Mac Ultra-Portable Drive is a highly portable external drive great for backing data on your Mac or even Windows computer and taking that data with you wherever you travel. In a durable, soft-touch finish, this drive features a fast disk speed of 7200rpm and an ample storage capacity of 500GB. This drive comes formatted for use with your Mac and can connect to your computer with either the included USB 2.0 adapter or with the included FireWire 800 adapter. While the drive can immediately work with Time Machine right out of the box for fast Mac backups, it also comes preloaded with an HFS+ file format driver that you can install on your Windows computer. After installing that driver, you can use the drive interchangeably on both Mac and Windows computers. For a reliable, fast, durable, portable, Windows and Mac-friendly external hard drive, check out this one from Seagate.