Keystone KTSB-E-2048-46-UV-S 4-6 Lamp T8HO/T12HO Rapid Start Sign Ballast - 120VKeystone Technologies KTSB E 2048 46 UV S 4 to 6 lamp electronic sign ballast. The high quality sign ballast works with 20" to 48" T8HO and T12HO lamps. Keystone's sign ballast are intended to repair business signs and other signage with bad ballast. The electronic ballast is a rapid start ballast comes with wire leads for 120~277 VAC applications. 4 year warranty Keystone KTSB E 2048 46 UV S 4 6 Lamp T8HO T12HO Rapid Start Sign Ballast 120V Keystone