Highest capacity. 4TB means you get the highest storage capacity available in the 3.5-inch Server class. (Note: This is a SAS interface HDD, it will not compatible with SATA Interface, please make sure your system has the SAS controller interface.) HIGHEST-RELIABILITY - The industry’s highest-reliability 7200-RPM drive, designed for 24×7 operation with MTBF of 2.0M hours and AFR of 0.44%. Stores up to 10 PB in a single 42U rack with helium technology Advanced Write Caching provides a 20% performance boost* Up to 21% improvement in IOPS/watt Works for RAID System, NAS Network Storage, Datacenter Storage, Servers (SAS Interface controller required) Bare Drive Only, Single Pack, (No Screws, Cables or Accessories included) -Friendly Reminder- Please FORMAT HDD on system in order to be detected/shows on system.