Hard Drives Up to 24 x 2.5" Enterprise Class HDDs or SSDs Backplane x24 way Backplane for up to 24 x 2.5" SAS and SSD Hard Drives Controllers 2 x SAS 6G Redundant Controllers Power Supplies Dual Redundant 600W PSUs External RAID Controllers N/A External SAS Controllers Options include Dell 6Gb/s SAS Dual Port Rail Kit Dell PowerVault 2U Rapid Rails Available Additional Information N/A