Keystone KTSB-E-0848-46-UV 4-6 Lamp T8HO/T12HO Instant Start Sign Ballast - 120/277VKeystone Technologies KTSB E 0848 46 UV 4 to 6 lamp electronic sign ballast. The high quality sign ballast works with 8' to 48' T8HO and T12HO signs. Keystone's sign ballast are intended to repair business signs and other signage with bad ballast. The electronic ballast is a instant start ballast comes with wire leads for 120~277 VAC applications. 4 year warranty. Brand: Keystone Type: Instant Light: Fluorescent Lamp: T8, T12 Ballast: Electronic