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The filter element is contained within a 10-32 external to 10-32 internal threaded fitting so that components may be stacked for maximum efficiency and compactness. The filter is pressed into the external threaded end of the fitting. The filter is used to keep foreign material out of the fluid stream where small orifices may get clogged by air line contaminants. 5, 20, 40 micron sintered filter elements and 43 micron wire mesh screens available.