Advance Magnetic Compact Fluorescent Ballast, Series: Standard, 2-Pin CFL Lamp, 13 W Lamp, 277 VAC, 0.3 A, 60 Hz Frequency, Pre-Heat Start, 32 deg F Minimum Starting, Total Harmonic Distortion: 10%, Power Factor: 0.27, 1 Lamp, Thermal Protection: Class P, 2-Pin GX23 Lamp Base, Ballast Factor: 1, ANSI C82.1 Ballast Grade, Metal, 3-3/4 in L x 1-3/4 in W x 2 in H Dimensions