The product is a lot of 2 Western Digital 16TB Ultrastar DC HC550 internal desktop drives in 3.5-inch form factor. These silver-colored drives have a rotation speed of 7200 RPM and a storage capacity of 16TB each. They are compatible with PCs and feature SATA III, SATA II, and SATA I interfaces. The drives come from the Ultrastar product line and have a cache size of 512 MB. Made in Thailand, these HDDs offer hybrid (HDD/SSD) and hot swap features, making them ideal for high-performance storage solutions.