WD Gold 20TB HDD WD202KRYZ, set of 2. These were kept for NAS maintenance. They have been used for a few startups and tests, but the operating hours are short and the operation is problem-free. Please see the CDI captures from the 7th photo onwards for the operating status. There is no outer box. Everything in the photos is included. WD Gold HDDs are built for use in enterprise-grade storage systems and data centers, and are widely compatible with major enterprise operating systems. Specifications: Capacity: 20 TB Form Factor: 3.5-Inch Connector: SATA Interface: SATA Transfer Rate: up to 269MB/s Disk Speed (RPM): 7200 RPM Recording Technology: CMR Cache Size: 512MB Endurance (TBW): 550TB/year Dimensions (LxWxH): 147mm x 101.6mm x 26.1mm Weight: 690g Product Model Number: WD202KRYZ Operating Temperature: 5°C to 60°C Thank you.