This is the Tridonic PC 3/4x18 T8 Pro, a non-dimmable high-frequency ballast to run 3 or 4 x 18w T8 fluorescent tubes. These ballasts have a nominal lifetime of up to 100,000 hours and provide a constant luminous flux even with fluctuations in mains voltage. Tridonic T8 Pro ballasts also have an automatic start after the replacement of defective lamps and a safety shutdown of defective lamps at the end of a lamp\'s life. All T8 pro ballasts are suitable for use in emergency fittings, in line with EN 50172 Tridonic article number: 22185219 Dimensions: L 280mm, W 30mm, H 28mm Click here to see Data Sheet and Wiring Diagrams!