The XEB42CFZ Compact Fluorescent Emergency Ballast allows the same fixture to be used for both normal and emergency operation. In the event of a power failure, it switches to the emergency mode and operates one of the existing lamps for 90 minutes. The unit contains a battery, charger, and inverter circuit in a single can. The XEB42CFZ can be used with most 10-42 watt, 4 pin, quad and triple tube, compact fluorescent lamps, with an initial output of up to 650 lumens for one lamp.