Free Shipping! WD 80TB Storage Capacity (20TB x 4), 3.5" Form Factor, SATA III 6 Gb/s Interface, 512MB Cache, 7200 rpm, Data Transfer Speeds up to 268 MB/s, 600,000 Load/Unload Cycles, 2.5 Million Hours MTBF, Multi-Axis Shock Sensor, NASware Technology