Fluorescent Emergency Ballast allows the same fixture to be used for both normal and emergency operation. In the event of a power failure, the ISL-28 switches to the emergency mode and operates one of the existing lamps for 90 minutes. Delivers high performance in a slim design. This unit is ideal for use in linear lighting fixtures ballast compartment space is limited. The unit contains a battery, charger, and inverter circuit in a single can. UL Listed for retrofit applications and can be used with most 2-4 ft. T5 and T8 fluorescent lamps at an initial output of up to 800 lumens for one lamp.