Black Flag 15W Outdoor Electric Insect Killer Replacement Bulb, White Light. Black Flag is the consumer recognized brand in the Bug zapper category. Our superior voltage lets you see the lights and hear the quiet zaps while protecting youryard. Black Flag Bug Zappers use new advanced circuit board technology to deliver superior performance and use 30% lessenergy and provide 20% more bulb life compared to competitors. Replacement bulb for black flag bug zappers. White lightattracts/kills 40% more flying insects. Easy to install.