The heavy duty electrostatic furnace filter and air conditioning filter is more efficient and longer lasting than the economy duty model. It is a more rigid and denser filter than other heavy duty electrostatic air filters. This electrostatic furnace filter and air conditioning filter is made of 1 ply of unique, rigid, fibrous filter media, then encapsulated by 2 layers of fine mesh polypropylene electrostatic filter fabric and 2 layers of expanded galvanized steel face grid. The inner air filter media, unique to Good Filter Company, is rigid and self-charging for excellent sturdiness and superior efficiency. Then comes 2 layers of fine mesh polypropylene electrostatic filter fabric for more small particulate capturing and holding capacity. Finally, 2 layers of heavy duty expanded galvanized steel face grid for protection of the inner layers and the capturing of large particles and enclosed in a heavy duty galvanized steel frame, making this filter a no-wrinkle and no-stretch, very sturdy and efficient electrostatic air filter. Unlike other manufacturer’s electrostatic air filters, the Good Filter Company heavy duty electrostatic filter washes clean with no buildup of residual particles keeping air resistivity at a minimum. No one else makes an electrostatic air filter like this one. The Good Filter Company heavy duty electrostatic furnace filter and air conditioning filter is available in many standard and custom sizes. Our electrostatic furnace filters and air conditioning filters with any dimension larger than 30″ may have a center brace for added strength, another Good Filter Company quality addition not found on other electrostatic air filters.