The Right Fit For Your High-Output Applications Programmed Start Operation - Helps to Extend Lamp Life In Frequent Switching Applications Such As Occupancy Sensors or Daylight Harvesting;Starting Capability At -20F - Suited For Cold Temperature Applications (54W Models Only);High-Low Switching - One Ballast Can Easily Switch From 4-Lamp to 2-Lamp Fixtures No Matter What The Conditions Require, Operating At A Variety Of Line Voltages Between 120V to 480V, Whether Located In High Ambient Temperature Environm