Nexsan E18X Expansion Unit with 18x 600GB SAS Disks. Nexsan Technologies E18 SAN Array - 18 x HDD Installed - 2U - Rack-mountable. These have a mixture of 600GB drives & 2TB drives. Im not sure what is in what but there is a total of 36 x 600TB drives and the rest are 2TB drives.
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