Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5 Internal - SATA. Data center decisions are driven by TCO. Higher capacity hard drives play a leading role in reducing TCO. An 18TB data center HDD provides 29% more capacity in the same form factor as a 14TB HDD. Higher capacity HDDs enable data centers to lower CapEx by reducing supporting hardware and system level costs when compared to lower capacity drives. Helium-sealed low power high reliability drives reduce energy and maintenance costs contributing to OpEx savings. For example a data center using 18TB HDDs vs. 14TB HDDs requires 22% fewer racks while consuming 21% less power per TB at idle resulting in significant overall TCO reduction for data center environments *** SINGLE PACK ***