Detailed Product Description 500 600 ventilatorSaving-Energy turbine ventilator IntroductionCompare use life-span of different ... materials, take 500 model as examplematerialWeight of turbine headperformancelife-spanColor steel plate4.0-5.5 kgRust easily ... oxidation,no rust,light weightOver 15 years No power turbine ventilator parameterModel 300,500,600 ventilator generally refers ...