This Seagate Barracuda 7200.9 internal desktop drive has a storage capacity of 160GB and a rotation speed of 7200 RPM. It is compatible with PC, Mac, and iOS systems and supports the ATA interface. The 3.5 inch form factor and 8MB cache make it a reliable option for storage. The ST3160812A model features hot swap and removable capabilities, allowing for easy maintenance. The silver color and Barracuda product line make it a sleek addition to any setup. This unit is sold as one and weighs in at one pound.