Dimming Ballast, Ballast Type Electronic Dimming, Ballast Family EcoSystem(r), Number of Lamps 1, Lamp Type T4 4 Pin Quad or Triple TubeVoltage 120-277, Height 1 In., Width 3 In., Length 5 In., Input Watts 21.3/21.1/21.4/20.8Amps AC 0.180/0.098/0.092/0.080, Start Type Programmed Rapid, Min. Starting Temp. 50 Degrees F, Dimming Range 100 Percent to 5 Percent RLO, Ballast Factor 0.95, Power Factor Greater Than 0.95, Total Harmonic Distortion Less Than 10 Percent Lutron Electronic Dimming BallastsDimming ballasts save energy while providing smooth, continuous, ultra-quiet dimming.UL Listed and CSA Certified.EcoSystem Dimming to 5% Ballast factor: 1.0 Use with Lutron fluorescent dimmers and digitally addressable systems