| (1) 1TB = 1 trillion bytes. Actual user capacity may be less depending on operating environment. Quality and reliability with up to 2.5M hours MTBF to help you store your data with confidence. | (3) MTBF and AFR: Projected values for model number WD221KRYZ and WD202KRYZ. Final MTBF and AFR specifications will be based on a sample population and are estimated by statistical measurements and acceleration algorithms under typical operating conditions, workload 220TB/year and device temperature 40°C. Derating of MTBF and AFR will occur above these parameters, up to 550TB writes per year and 60°C device temp. Specifically designed for use in enterprise-class storage systems and data centers. Improve performance with our vibration protection technology. HelioSeal technology delivers high capacities with a low power draw (12TB & up). Hard disk interface Serial ATA-600 Connectivity technology SATA Brand Western Digital Hard disk form factor 3.5 Inches Hard disk description Mechanical Hard Disk Compatible devices Server Installation type Internal Hard Drive Colour Gold Hard disk size 20 TB Hard disk rotational speed 7200 RPM