... about 20000Hrs.3.High power factor,Low THD ,the electronic ballast can work steadily when the voltage range varies from 160V ... -250V.4.The electronic ballast works in high frequency beyond 20KHZ,quietly, no negative ... EMC2×40W Electronic ballast with PF0.98,THD<20%,CCF<1.7,quick/preheat start (option),with CE approval,3years warranty.... Electronic ballast 4X40W/ ...