Duo4 4 Inch Furnace Filter This 20" x 25" x 4" .
Furnace filter is our best air filter for HVAC systems.
4 or 5 inch air filter slots .
Disposable filter with 2 layers.
Safe Home Duo4 4 Inch Furnace Filter This 20" x 25" x 4" furnace filter is our best air filter for HVAC systems with 4 or 5 inch air filter slots . This disposable filter with 2 layers to absorb dirt and chemical fumes offers up to 6 times the strength of our already powerful one inch thick Duo furnace filter. Designed to replace either 4" or 5" filters, the Duo4 traps hazardous chemicals, odors and allergens unlike any other filter. The Safe Home(TM) Duo4 looks different because it is different. Safe Homes filters are the only home air replacement filters that capture allergens, odors, and harmful chemicals. The Duo4 features a superior design with self sealing edges for maximum effectiveness at capturing allergens, odors, and chemicals from the air in your house. Use for furnace filter slots, temporary needs, or custom sizes in air return grills. The Duo4 replaces any 4" thick home air filter in any location and can last up to 3 months. How does the Duo4work? - The polyester outer layers remove 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 Duo4 Filter Features: Dimensions: 20" x 25" x 4" 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 that can cause health issues. Highly effective and affordable. Twin filter pad: MERV 8 polyester white ASHRAE
