These Leybold AF10 oil mist exhaust filters are designed for the Leybold Trivac rotary vane vacuum pumps having KF-25 inlet and outlet flanges. Oil sealed rotary vane pumps, such as the Trivac, inject vacuum pump oil inside the vacuum pump to cool and seal the rotating components. Mechanical motion causes the injected pump oil to mix with the flow of air that is being pumped through the vacuum pump which generate an aerosol of vacuum pump oil (microscopic drops of oil suspended in the exhaust gas flow).

The exhaust mist filter media causes this oil mist aerosol to coalesce, where microscopic drops of pump oil combine to turn into large oil droplets that can no longer be suspended in the exhaust air flow. The Leybold AF10 exhaust mist filter has a separation efficiency over 99 percent, is shipped complete ready to use with internal exhaust mist filter element, and has Leybold part number 19051.