Norco 4U Rack Mount 20-Bays SATA/SAS Server Chassis RPC-4220 Case Type: 4U Rack mount Motherboard Compatibility: Support EEB (12"x13"), CEB(12"x10.5"), ATX (12"x9.6"), Micro ATX (9.6" x 9.6") Drive Bays: 20x hot-swappable SATA/SAS drive bays, 1x slim CD-ROM bay, 2x 2.5" OS drive brackets Connector: 1x front accessible USB port, 5x internal SFF-8087 Mini SAS connectors, 10x 4-pin redundant Molex power connectors Switch: 1x Power ON/OFF, 1x System reset Indicator: 1x Power ON/OFF, 1x HDD, 2x NETWORK Cooling Fan: 4x 80mm middle fans wall, 2x 80mm rear fans Power Supply: None