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21.25x21.25x1 Air Filter Merv 8
21.25x21.25x1 AC Filter Merv 11
21.25x21.25x1 Furnace Filter Merv 13
21.25x21.25x1 Filter Merv 13 Titanium
21.25x21.25x1 Filter Merv 10 Carbon

21.25x21.25x1 Air Filter MERV 8

AC Furnace Air Filter 21.25x21.25x1 -Inches MERV 8

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Product Description

Item Model Number: FKFB21.25X21.25A
Brand: Filter King
Filter size: 21.25x21.25x1
Actual Size: 21.25 x 21.25 x .75
1-Inch Filter
MERV 8 Filter Rating
Protection From: Pollen, Dust, Mold, Dust Mites, Bacteria, Pet Dander, Smoke, Viruses
Residential / Commercial Use

Manufactured in the US

21.25x21.25x1a Air Filter Reviews

21.25x21.25x1 Air Filter

Filter King 21.25x21.25x1 size air filters are used by accompanying air systems to keep pumped in air clean. The filters consist of a tight mesh weaving designed to capture and absorb a range of irritants entering your home via airflow. Air filters work constantly as the air continues to come in, cycling fresh air throughout your home. The process raises your home’s indoor air quality and keeps the air coming in free of harmful particles. Your air filters become dirtier over time, and will eventually need replacement before they start causing problems.

When the air filters in your home become dirty, they end up causing several problems for their systems and your home. The dirty filters will block off airflow, which means that the air inside your home will be unable to cycle out leading to dryness and stagnation. Your air systems also face issues as they attempt to push airflow past the blockages and into your home. The efforts will lead to mechanical damage for your systems and a rise in energy billing over time.

The air systems in your home work best when the air they bring in is allowed through new air filters without any problems. We offer fresh, new 21.25x21.25x1 size air filters for sale at affordable prices and ready for use upon arrival. Filter King also has premium delivery services, with a subscription option to have new filters arrive at your home as often as monthly. Our filters rate as an eight on the MERV (Minimum Efficiency Reporting Value) scale. This means that they filter out particles like:

  • Pollen
  • Dust
  • Mold
  • Dust Mites
  • Bacteria
  • Pet Dander
  • Smoke
  • Viruses

21.25x21.25x1 Furnace Filters

Furnace air filters have the important function of cleaning up heated airflow passing through the system. The furnace air filters clean up heated airflow before its distribution, which prevents irritants from polluting your home. Over time, the furnace air filters in a system will become dirty and begin blocking the heated. The resulting rise in internal temperatures will cause mechanical damages and temperature fluctuations throughout your home. Order new air filters now and have them delivered promptly before easy installation.