60mm iron sheet length magnetic ballast: 1,watts:40W/30W/20W 2,power factor:0.54/0.48/0.37 3,OEM service provided 1, Energy saving : low power loss , high light efficiency2, Low exotherm , no stroboflash , no noise3, Convenient fixing , easily control , long service time4, High quality model can reach CE & ROHS standard. 60mm iron sheet length magnetic ballast C140 C130 C120