Advance Magnetic Compact Fluorescent Ballast, Series: Standard, CFL Lamp, 26 W Lamp, 120 VAC, 0.24 A, 60 Hz Frequency, Pre-Heat Start, Total Harmonic Distortion: 25%, Power Factor: 0.83, 1 Lamp, Thermal Protection: Class P, G24d Lamp Base, Ballast Factor: 0.83, ANSI C82.1 Ballast Grade, Metal, 6.5 in L x 2.38 in W x 1.5 in H Dimensions