Model: Western Digital Ultrastar DC HC570 WUH722222ALE604 -- 22TB enterprise-class 3.5″ SATA hard drive. Model WUH722222ALE604. Storage Capacity 22TB. Interface: SATA 6 Gb/s (SATA III) with 7,200 RPM spindle speed and 512 MB cache for high throughput and reliability.
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