Screw air compressor maintain kit include lubricant oil, air and oil filter. Oil separator filterScrew air compressor maintain kit include lubricant oil, air and oil filter. Oil separator filter
The air oil separator is a filter like part which separates the oil from the compressed air.
During compression oil is injected to lubricate, seal and absorb the heat of compression, then what comes out of the compressor element is a mixture of compressed air and oil. The oil separator separates the oil from the air as the oil needs to stay inside the compressor to keep it lubricated while the compressed air needs to exist the compressor, free of oil.