70-400W Ballast

70-400W Ballast: High quality, copper and aluminum type available, for metal halide lamp and sodium lamp 70-400W All the silicon steel sheets used for electromagnetic ballasts are of extra good quality and made under high speed press. The products are painted in vacuum by automatic impregnating paint machine. it can reduce noise and avoid shake.it can decrease the temperature risethe surface is smooth and with no paint bubble.it can reduce the number of windings and avoid short circuit.