... oil, odourless and tasteless. Functioning as the last filter step, it services the industry using high-quality air, such as ... small as 1μm, so as to achieve the minimum residual oil content of 0.5ppm, including ... 3μm or More,so as to achieve the minimum residual oil content of 5ppm only, including ... and oil mist. After the use of after-cooler, and before the use of the other filters and cold and ...