The Seagate Video 1TB ST1000VM002 SATA 3.5" PC CCTV DVR HDD is a high-performance internal desktop drive designed for use with PCs and Macs. With a storage capacity of 1TB, this silver HDD features a rotation speed of 5900 RPM and a cache size of 64MB. It is part of the Video 3.5 product line from Seagate, making it an ideal choice for storing large amounts of data for video surveillance systems or other storage-intensive applications. This unit is a reliable and efficient solution for expanding storage capacity in your system.