Optimized for use in ground mobile/vehicular, portable system, and other high shock and vibration applications, the GMO Rugged Enclosures consist of an exterior shell for mounting and shielding, and an interior sub-chassis that houses a VMEbus or CompactPCI card cage. The shock- and vibration-isolated card cage complies with MIL-STD-810E. Mechanical isolators joining the two assemblies meet MIL-STD-167 and reduce transmission of high-energy shock and vibration to the interior sub-chassis. Flow-through air cooling provides more than 200 cfm through the enclosure. Standard power is 500W with an input of 28 vdc, with option of 1000W. Backplanes hold up to 15 VMEbus slots or eight CompactPCI slots.