Western Digital 1TB Portable USB External Hard Drive Western Digital 1TB 移动硬盘 （Portable USB External Hard Drive） This expansive external hard drive offers increased storage space for movies, photos and other digital media, and the fast transfer speeds mean that it's easy to swap files back and forth when needed. • USB 2.0 and USB 3.0 compatibility allows use with a wide range of devices. • Data transfer speeds of up to 5GB/second let you quickly move data from device to device. • 64MB cache