The Flanders Precisionaire Heavy Duty Fiberglass Filters are designed for use in any application where disposable panel filters are recommended. They can be relied upon for superior performance as they are specifically designed for heavy workloads. The fiberglass media filter consists of continuous filament fibers bonded together with thermo-setting resin and enclosed with a one-piece moisture-resistant chipboard frame. Support grilles of perforated corrosion resistant steel or expanded metal are provided on both sides of the filter. The media pads and support grilles are continuously glued to the inside perimeter of the frame, resulting in exceptional strength and rigidity. This design virtually eliminates the possibility of media sag within the frame. A wide range of standard face sizes are available, plus nearly any special size.