Samsung S2 Portable Hard Drive 640 GB USB 3.0 External Hard Drive (HX-MTA64DA/G32) Powered via USB - no extra cords needed AutoBackup and SafetyKey software keeps data safe and prevents unauthorized access USB 3.0 technology for faster speeds 640 GB of data storage in a compact drive Stylish streamlined design and anti-slip grip for effortless portability 640 GB of data storage in a compact drive USB 3.0 technology for faster speeds Stylish streamlined design and anti-slip grip for effortless portability AutoBackup and SafetyKey software keeps data safe and prevents unauthorized access Powered via USB - no extra cords needed Backed by a three-year limited warranty