Like the Ultrastar 7K4000 line, the new RE SAS and SATA 4TB drives, contain five 800GB platters.

Both the SAS and SATA drive products use the latest 6Gbps-interface specification.

Unlike the Ultrastar drives, the new RE SAS and SATA drives do not have a native encryption option. WD said it would be offering encryption on the RE SAS model in the future.

"The WD RE SAS and SATA 4 TB drives are designed, tested and optimized for enterprise storage and applications, enabling 33% greater capacity than previously available drives and up to 2.4 PB of raw capacity in a single enterprise rack," Doug Pickford, a senior director of business marketing for WD, said in a statement.

Dell is one of WD's resellers offering the new drives in its , offering up to 240TB of capacity in a single array.