Kichler Lighting 4033 Anti-Turn 13-Watt Compact Fluorescent Ballast can only be used with compatible CFL bulbs. The 4033 is 2.5IN long x 1.75IN diameter. The 4033 comes one package. Since 1938, Kichler Lighting has offered a distinctive array of lighting solutions that reflect your individual personality, tastes and plans. Kichler brings you an unparalleled variety of exciting style families, unique finishes, fresh colors and unequaled quality. Whether it"s casual, contemporary, transitional or traditional, you"ll find it with Kichler, lighting that defines your style.