iStarUSA DN-400-55R8P Black SGCC 1.0mm 4U Rackmount 4-Bay Compact ATX Chassis with 550W Redundant Power Supply 550W Redundant 4 External 5.25 Drive Bays Motherboard Compatibility: 12 x 9.6 (ATX, microATX, mini-ITX) Power Supply: 550W Redundant External 5.25 Drive Bays: 4 Internal 3.5 Drive Bays: 6 Expansion Slots: 7 Front Ports: 2 x USB 3.0 Dimensions (H x W x D): 5.25 x 18.98 x 19.43