GE Lighting 89720 GEM1FC16T9RS120 LFL Magnetic Rapid Start Ballast for 2 - FC12T9, FC16T9, FC8T9, FC12T9 Mount length: (M) 6.0-Inch / Mount slots: (MS) 0.3-Inch GE's ballasts are among the highest energy-efficient ballasts available For 1- FC8T9, RS Starting method: Rapid start Ballast type: Magnetic