Constructed of rugged steel, the RackMac mini places the computers behind a smart front panel. The enclosure?s design manages airflow through the computers to keep them as cool as ambient air - stack them close and stack them high for a Mac mini server farm. The RackMac mini provides a front panel power switch and front panel USB 3.0 port for each computer; built in panel-mount cables connect the ports to your computers' USB ports.