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• Never needs replacing
• Removes dust, pollen, and airborne pollutants
• Unique electrostatic capabilities
• Made of anti-microbial material
• No harmful ozone or emissions
• High dust and particulate holding capacity
• No electricity required
• Easy wash and clean design
• Tested to meet MERV 8 rating
• Available in 60 different sizes
• Multiple thicknesses available including flex
• Lifetime warranty


PermaFilters clean the air by using static electricity as a safe, naturally occurring phenomenon. An electrostatic charge is generated by air flowing through a maze of static prone fibers. This unique characteristic improves air flow while providing maximum filtration. Airborne particles are attracted and held by the static charge, until released by washing. PermaFilter is rated by ASHRAE standards to meet MERV 8 specifications for particulate removal.

With over 60 filter sizes available including multiple thicknesses, PermaFilter is designed to fit any application. The permanent electrostatic design is rated MERV 8 to remove airborne particles, including dust, pollen, soot, pet dander, lint, spores, and other harmful particles in the air. The PermaFilter never needs replacing, and by following the cleaning instructions, you can easily remove the soil load for the next use.

See Product Bulletin to see all part numbers and sizes available.

Packaging Size Part Number Additional Info
14x20x1 4940-08 1" Metal Frame
16x20x1 4940-12 1" Metal Frame
14x24x1 4940-14 1" Metal Frame
14x25x1 4940-15 1" Metal Frame
16x25x1 4940-19 1" Metal Frame
20x20x1 4940-20 1" Metal Frame
14x30x1 4940-21 1" Metal Frame
20x24x1 4940-24 1" Metal Frame
20x25x1 4940-26 1" Metal Frame
20x30x1 4940-28 1" Metal Frame
16x25x4 4940-40 4" Metal Frame
20x25x4 4940-42 4" Metal Frame
20x25x5 4940-47 5" Metal Frame
16x25x1 Flex 4940-57 1" Flex Frame
20x20x1 Flex 4940-58 1" Flex Frame
20x25x1 Flex 4940-59 1" Flex Frame


1. Remove the old disposable air filter.
2. Review the PermaFilter product label for air flow direction arrows.
3. Insert the new PermaFilter in place according to proper air flow direction.

It is suggested to clean the PermaFilter every 8-12 weeks. When cleaned as directed, your PermaFilter will give you many years of trouble-free use. Failure to properly clean the filter may lessen filter effectiveness, and as with any air filter, it is possible for an excessive dirt buildup to cause air flow resistance sufficient to damage other ventilation components.

1. Simply remove the PermaFilter from the system.
2. Flush with water in opposite direction of air flow arrows.
3. Rotate PermaFilter and rinse with water in the opposite direction.
4. Spray the filter with Nu-Calgon Green Clean 4186-24, or a light duty detergent-based cleaner
5. Rinse thoroughly to remove remaining dirt on the PermaFilter.
6. Drain excess water and let air dry.
7. Once dry, Bio-Fresh cd 4126-34 can be applied to the filter for odor control and residual bacteria protection.

Product Information:

Literature Downloads

Download the product bulletin and other relevant literature here.


Product Safety

RTK Information

2611 Schuetz Rd. St. Louis, MO 63043
  • Telephone: 800.554.5499
  • Email: [email protected]
  • Hours: Mon–Fri: 8:00am - 5:00pm (Central Time)

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