Abstract: A filter is provided. The filter includes a first layer of a non-blocking screen and a second layer of the non-blocking screen disposed against and in direct contact with the first layer, said first and second layers together forming a filter.

Abstract: A generally planar expanded metal filter media support structure is provided. The filter media support structure includes a first row of perforations mutually separated, one from another, by a perforation distance along a first axis parallel to the plane of the support structure and at least a second row of perforations parallel to the first row of perforations offset from the first row of perforations along the first axis by a first offset distance greater than zero and less than one-half the perforation distance and offset along a second orthogonal axis in the plane of the support structure by a second offset distance.