The Dell Poweredge 900GB SAS 2.5" Hard Drives are tested and wiped to D.O.D. standards. The 900GB SAS 2.5" Hard Drives come in 10,000 (10K) and 15,000 (15K) rotational speeds. The Dell SAS 2.5" Hard Drives come in data transfer speeds of 6GBps and 12GBps. If you have any questions on Hard Drives call us at 952-831-1032.