Seagate Expansion 500GB Portable External Hard Drive USB 3.0 (STEA500400) Easy and simple to use - plug it in and go Fast file transfers with SuperSpeed USB 3.0 Compatible with USB 3.0 and USB 2.0 Powered by USB port Drag and drop file saving for Windows, right out of the box. Please note: Product needs to be reformatted if it is to be used with Mac. Reformatting the drive will erase all content unless it is backed up to another drive.