The Seagate ST4000VX005 4TB 3.5" SATA Skyhawk Surveillance Hard Drive is a high-performance internal desktop drive designed for use with PCs. With a storage capacity of 4TB, this HDD offers fast data access and transfer speeds at 7200 RPM. The drive features a 3.5-inch form factor and is part of the Western Digital brand's Seagate Skyhawk product line, known for its reliability and durability. Additionally, the drive includes an in-built media server and a cache of 256 MB for improved performance.