Replacement One Inch Air Pollution Removal Furnace Filter, 14 x 18 x 1 Inch Made In USA, The Safe Home TM Duo is a 14 by by 1 inch disposable furnace filter for a one inch furnace filter slot. The Safe Home Duo air purifier furnace filter looks different from standard 1 inch furnace replacements.This unique air filter incorporates two air purification filters covering a steel frame. The white polyester pre-filter capture allergens the black 50/50 potassium permanganate and activated carbon filter removes odors, and harmful chemicals. Self sealing edges maximize effectiveness at capturing allergens, odors, and chemicals from the air. For one inch furnace filter slots, temporary needs, or custom sizes in air return grills. The Duo replaces any 1 thick home air filter in any location and can last up to 3 months. Note Check with your HVAC technician to verify that your system is able enough to handle the density of a MERV 8 filter before purchasing this or any other MERV 8 filter.Install this MERV 8 with Air Flow First Going through the White Media. Made in USA. How does the Duo work? The polyester outer layer removes pollen, mold spores, and other common allergens. The inner layer features FormaldaSorb TM and activated carbon that traps a variety of odors and hazardous gasses, such as formaldehyde, ammonia, and others that are emitted by cleaning chemicals, paint, particle board, and other household items. No other filters are as effective at removing dust mites, mold spores, pollen, odors, cleaning chemicals, ozone, paint fumes, and common gasses like formaldehyde which triggers asthma and allergies. Safe Home Duo Furnace Filter Features Dimensions 14 x 18 x 1 Captures up to 95% of common household allergens Eliminates odors from pets, paint, cooking, and more Uses high density carbon and advanced compounds FormaldaSorb TM , a patented potassium permanganate product plus the activated carbon in the second layer of the filter trap gasses t