EarthTronics LED emergency drivers regulate the power supplied to the LED fixture so that it can operate as a light source in the event of a power failure. The purpose of emergency lighting is to insure that lighting is provided promptly, automatically and for a suitable time when the normal power supply fails. This insures that people within the building can evacuate safely in the event of an emergency. All EarthTronics emergency drivers meet specific UL, CSA and NFPA requirements. Always consult local code requirements when specifying emergency lighting products. 100-277V Only.