FS.COM supplies M6 models of screw and nut. The "M" designation for metric screws indicates the nominal outer diameter of the screw. For example, an M6 screw has a nominal outer diameter of 6 millimeters.
These M6 screws and nuts for server racks and cabinets are convenient to have on hand for installing a server, network, AV, and other rackmount equipment securely into your storage cabinet or server rack.