Recessed 9 Cell Parabolic 2X2 For Three F17T8 Lamps, 120 Volt Electronic •Contains 3-F17T8 electronic ballast with 5 year warranty. •Parabolic louver reduces glare on computer monitors. •Silver parabolic louver with white steel body. •F17T8 lamps are less expensive and easier to handle than U-lamps. •Designed for lay-in grid. •23.75" square by 5.5" overall height. •Also available in 277 volt.