Philips Advance Centium 110-Watt 1- or 2-Lamp T12 8 ft. HO Rapid Start High Frequency Electronic Fluorescent Replacement Ballast 520486 - The Home Depot
Philips-Advance E-Vision RMH20KBLSM 22w Philips Mini MC C175 electronic HID ballast
Philips Advance - 2 Lamp, 120 Volt, 0.43 to 0.48 Amp, 0 to 39 Watt, Trigger Start, Magnetic, Nondimmable Fluorescent Ballast - 03749850 - MSC Industrial Supply