A High Efficiency Filter is an investment in healthful comfort for your family and protection for your home and furnishings. This air cleaner is many times more efficient than ordinary furnace or air conditioning filters with which you may be familiar. High efficiency air cleaners incorporate a filtering media made from microscopic fibers woven into an intricate web that traps and holds airborne particles of dust, pollen, animal dander, etc. The spaces between the fibers are so small that particles as tiny as 0.01 micron are easily captured. By comparison, a particle 300 microns in diameter (30,000 times larger) would fit easily through the eye of a sewing needle!