... CE,TUV listed No fans inside HPS/MH electronic ballast.Welthink series digital electronic ballast can run HPS and MH bulbs both automatically ... circuit protection functions available.Easy installationEasy to hang the lamp, no need any external starter and compensation capacitor.Completely ... soluaitons are available UL CUL CE TUV listed HPS/MH electronic ballast,250W,320W,400W,500W 600W, 800W,1000W