The PQI 2.5" external portable hard drive-H551 is lighter in weight and smaller in size when compared to other 2.5" portable hard drives on the market! Approximately the size of one's palm , it does not take up any space and is easy to carry !The exclusive TurboHDD USB software can boost transfer rates up to 53% over most USB2.0 communication interface which saves users time when transferring mass data. Current maximum storage capacity is 640GB. H551 has a streamline look and blasted treated surface which brings out the shinning silver I royal blue craftsmansh ip for individuality ! It comes with a 3-year warranty and users can easily upgrade by themselves once the warranty period has expired with its screw-less design. At the press of a button ,the case can be easily opened to install a replacement hard drive . Unlike most portable hard drives requiring tools to access internal components , the operation is effortless !