The Seagate Portable Backup Plus 4TB USB HDD (STHP4030400) is a sleek black external hard drive with a compact 2.5-inch form factor. It is powered by USB and offers a storage capacity of 4TB, making it ideal for backing up and storing large amounts of data. This portable hard drive from Seagate is easy to use and perfect for those looking to expand their storage capabilities on the go. It is designed for convenience and efficiency, with features like USB 3.0 and 2.0 interfaces for fast data transfer.