2.5 inch Slim Portable Hard Drive for Mac (External) 500GB Capacity USB (Universal Serial Bus) 3.0 Interface (backwards compatible with USB (Universal Serial Bus) 2.0) Store or back up photos, movies, music & documents Download & save content that's posted on your social networks Share your digital memories to your social networks with a click The Slim for Mac is Time Machine-ready right out of the box, so you can just set it up & forget it