Ultrastar DC HC550 integrates a suite of technologies on a 9-disk platform to create a new class of HDDs. 18TB capacity is achieved by combining technologies that improve areal density working together with technologies that improve performance and reduce power consumption.
7200 RPM
256 MB Cache
6Gb/s Data Transfer Speed
18/16TB capacity¹ in a standard 3.5-inch form factor
 CMR technology works with all capacity enterprise applications & environments 
Reliable, field-proven, 6th generation design 
Industry’s first HDD with Energy-Assisted Magnetic Recording technology