The Liebert GXT420R1WRK3WE Rack/Tower UPS is a true on-line UPS with a 500VA 3000VA power capacity that delivers continuous, high-quality AC power to IT equipment with no break when transferring to battery power. It protects equipment from all power disturbances such as but not limited to blackouts, brownouts, sags, surges, frequency deviations, or noise interference. Features: Installs in either rack or tower configuration. Intelligent fan operation, automatically changes fan speed to decrease power consumption and noise.Operation and display panel with LCD for monitoring load percentage, system voltages, alarm notifications, and battery capacity.Allows customization of UPS features including output voltage selection, active ECO mode, auto-restart enable/disable, and other parameters.UPS provides easy serviceability with user replaceable hot-swappable batteries.