The Western Digital WD My Book 4TB External HDD is a desktop external hard drive that offers 4TB of storage capacity. It features a USB 3.0 interface for fast data transfer, a sleek black design, and a 3.5-inch form factor. With a rotation speed of 5400 RPM and a maximum fan speed of 5800 RPM, this HDD is designed for reliability and efficient performance. Compatible with PCs, this My Book model is perfect for expanding storage capacity and accessing your files with ease.