Western Digital Ultrastar DC HC580 24TB 3.5 SATA 6Gb/s Enterprise Hard Drive, 7200 RPM, 512MB Cache, CMR Technology, OptiNAND, Energy-Assisted Magnetic Recording (EAMR), Triple-Stage Actuator, HelioSeal Helium-Sealed, 298 MB/s Transfer, 2.5M Hours MTBF