The Western Digital Ultrastar DC HC550 is an 18TB enterprise-class hard drive engineered for demanding data center, cloud, and hyperscale storage environments. Built on a helium-sealed 9-disk platform with Energy-Assisted Magnetic Recording technology and a Triple Stage Actuator, the HC550 delivers maximum storage density and outstanding total cost of ownership in a standard 3.5-inch form factor. Running at 7,200 RPM with a SAS 12Gb/s dual-port interface and a 512MB cache, this drive provides fast, reliable access to massive datasets around the clock. This variant features hardware-based Self-Encrypting Drive (SED) technology with TCG Enterprise SSC support for secure data protection and compliant drive retirement — ideal for regulated industries and security-conscious deployments. Rated for 24x7 continuous operation with a 2.5 million hour MTBF and 550TB/year workload rating, the HC550 delivers the reliability and capacity modern enterprise storage demands.