The Guardian Electric A420-066028-00 is a three-phase uninterruptible power supply designed to provide reliable, clean power to electronic equipment. The A420-066028-00 offers four unrestricted outlet receptacles, output voltage regulation, and a temperature-compensated battery charger. Its mechanical design includes an enclosed steel housing and control enclosure, removable access panel, quiet operation, and wall mounting design. The A420-066028-00 also includes an adjustable overload capacity switch, audible alarm, and front-panel status indicators for power availability.