HGST Ultrastar 3.5-Inch 3TB 7200RPM SATA III 6Gbps 64 MB Cache Enterprise Hard Drive with 24x7 Duty Cycle (0F12456) 3TB Capacity 7200 RPM performance Dual Stage Actuator (DSA) and Enhanced Rotational Vibration Safeguard (RVS) forrobust performance in multi-drive environments 24x7 accessibility for enterprise-class, capacity-optimized applications 5-year limited warranty