Power factor is 99% efficient Silent operation with built-in axial fans for cooling Built-in safety features Built-in short circuit protection Constant wattage output. No flickering (stroboscopic effects), resulting in perfect illumination Weighs significantly less than magnetic core ballasts Built-in fuse protection Thermal overload protection 400/600 watt - 2 year factory direct warranty. 1000 watt - 1 year factory direct warranty New models can operate on both 120 & 240 UNIQUE FEATURE! All Future-Brite ballasts offered by Sunlight Supply include our proprietary female lamp cord receptacle. It will accept our proprietary, patented male lamp cord, making these units compatible with all Sun System reflectors.