Free Express Shipping! WD 18TB UltraStar DC HC550 7200 rpm SATA III 3.5" Internal HDD (OEM) 18TB Storage Capacity, 3.5" Form Factor, SATA III 6 Gb/s Interface, 512MB Cache, 7200 rpm, Up to 269 MB/s Data Transfer Speeds, 2.5 Million Hour MTBF, HelioSeal...