WD SE WD4000F9YZ - Hard Drive - 4 TB - SATA 6Gb/s

• Dual processor
  Twice the processing power to maximize performance.
• RAFF rotational vibration cancellation technology
  Enhanced RAFF technology includes sophisticated electronics to monitor the drive and correct both linear and rotational vibration in real time. The result is a significant performance improvement in high vibration environments over the previous generation of drives.
• Dual actuator technology
  A head positioning system with two actuators that improves positional accuracy over the data track(s). The primary actuator provides coarse displacement using conventional electromagnetic actuator principles. The secondary actuator uses piezoelectric motion to fine tune the head positioning to a higher degree of accuracy.
• StableTrac
  The motor shaft is secured at both ends to reduce system-induced vibration and stabilize platters for accurate tracking during read and write operations.
• Multi-axis shock sensor
  Automatically detects the subtlest shock events and compensates to protect the data.
• RAID-specific, time-limited error recovery (TLER)
  Prevents drive fallout caused by the extended hard drive error-recovery processes common to desktop drives.
• NoTouch ramp load technology
  The recording head never touches the disk media ensuring significantly less wear to the recording head and media as well as better drive protection in transit.
• Thermal extended burn-in test
  Each drive is put through extended burn-in testing with thermal cycling to ensure reliable operation.
• Dynamic fly height technology
  Each read-write head's fly height is adjusted in real time for optimum reliability.

WD's SE hard drives provide an ideal solution for scaleout datacenters, delivering a cost-effective combination of performance, reliability, and workload capability while maintaining the hardiness of a true enterprise-class design. All WD datacenter storage devices are designed from the ground up to deliver optimal performance and maximum data integrity while running 24 x 7 x 365 in demanding multi-slot environments.