... CWA Ballast. Inside with Scandium and Natrium Gas,very High luminous lux. Professional HID manufacturer, full range of American Standard mh bulb 50 ,70 ... ,250,400,1000,1500,2000WFeatures of American Standard Metal Halide Lamps1)Can both Matc European Standard magentic ballast and American standard CWA Ballast.2) Excellent color ...