EXAIR's Filter Separators remove water, dirt and rust from your compressed air system. They prevent these contaminants from plugging or damaging the compressed air products. A filter separator should be installed prior to an oil removal filter, pressure regulator or valve. The Model 9003 Manual Drain Filter has a polycarbonate bowl and a 20 micron element. A manual drain is used to empty the filter. Model 9001, 9002, 9004, 9032 and 9066 Automatic Drain Filter Separators have a metal bowl and a 5 micron filter element. An internal float automatically activates the drain when the bowl becomes full.