Abstract: The present invention relates to etched disc stack filters and particularly to such filters in which the etched discs include multiple arms in which are etched flow channels for the passage of a medium to be filtered and the removal or separation of a contaminant. In a particular embodiment of the invention, the etched discs may have an overall shape that is circular and may have filtering arms which radially extend from the center of each disc to the exterior border of the disc. The filtering arms may separate inlet and outlet openings. End caps may be attached at the ends of the disc stack and these end caps may have openings corresponding to the inlet and outlet openings in the discs in the disc stack.