Add 3TB of storage to your desktop, All-in-Once PC, secondary storage device, external drive, or backup device with the 3TB Green 3.5 inch OEM Internal Hard Drive from WD. Compatible with computers running Windows and Mac OS, this drive connects to your system's 3.5 inch bay via the SATA 6 Gb/s interface and features a sustained internal data transfer rate of 147 MB/s. So that frequently-used bits of data may be quickly recalled, this drive features a 64MB cache, which also helps ensure uninterrupted data transfers. Data performance is rounded off by a Dual Stage Actuator, which delivers high precision motion for increased data performance and increased drive reliability.