Camfil’s proprietary high loading SR media is assembled in a tapered pocket design. The combination of the SR media and the tapered pocket design provides full media usage and longer filter lifer. Secondly, the filtering efficiency of this product will never drop below the rated specifications, unlike electrostatically charged synthetic products which compromise the life of secondary HEPA filters and safety of building occupants. Pockets are assembled into a robust ABS header capable of withstanding >15.0″ w.g. without failing.