This listing is for a 3/4" coalescing filter / oilesser. This filter is used to remove oil from your air compressor air line system. This filter features one 3/4" inlet port and one 3/4"outlet port. The max air flow for this filter is 140SCFM. This coalescing filter has an easy twist drain at the bottom to empty it when it is full and it also has a rising red indicator that lets you know when the filter element needs to be changed. There is a clear window on the bowl for easy viewing of oil level. This is a must have for painting, sandblasting, and other compressed air uses to remove oil, and oil aerosols from your compressed air. Replacement filters are available when needed. Contact us at anytime!