Seagate 22.0TB 7200 512MB SATA3 EXOS 512E Enterprise ST22000NT001. Choose a robust, scalable, high-performance solution with the Seagate IronWolf Pro 20TB hard drive. Designed for professional NAS systems with unlimited bays, this 3.5" drive is capable of supporting a multi-user workload of up to 550 TB/year.