HGST HGST Ultrastar He6 6TB 3.5" SATA 7200 RPM Enterprise Internal Hard Drive with 64Mb Cache - HUS726060ALA640/ 0F18335 64 MB Cache 3.5-Inch Internal Bare or OEM Drives 0F18335 Industry's leading 6TB capacity in a standard 3.5-inch form factor with Patented HelioSeal technology Industry's best Idle and Active power efficiency (Watts/TB) Reliable, field-proven, 2nd generation HelioSeal process and 7Stac disk design enables the world's highest capacity 2M hours MTBF rating & 5-year limited warranty Advanced format 4Kn and 512e models