The SilverStone RM51 5U Rackmount Server Chassis in Black is specifically designed to support SSI-EEB motherboards and provide enhanced liquid cooling compatibility. It comes equipped with two high-performing Air Penetrator 184i PRO fans for efficient air intake, as well as the option to install a 360mm liquid cooling radiator. With 8 PCI expansion slots and reserved sliding rail mounting holes for quick installation, this chassis offers versatility and ease of use. It also features a USB Type-C interface and can be placed upright or horizontally. Additionally, if the 3.5" drive cage is left unoccupied, a secondary PSU can be installed.