Lithonia Lighting FM72 ACLS LP M4 Low-Profile Energy Star 20-Inch Square Fluorescent Light, White Include circline T9 4100K fluorescent lamp(s) for energy efficiency, superior color rendering long life Standard with electronic ballast (120-Volt, 60Hz) ensures no flickering Quiet operation without interfering with other home electronics For use with non-dimmable switches only All mounting hardware included