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AC Furnace Air Filter
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Product Description

Filter Size: 20×21.5x4A

Actual Size: 20×21.5×4

Actual Size Fraction : 20×21-1/2×4

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20×21.5×4 Air Filters

Elevate your indoor air quality effortlessly with our advanced 20×21.5×4 air filters, now available for convenient online purchase at Custom Filters Direct. These meticulously crafted filters are designed to deliver optimal performance, ensuring cleaner and healthier air in your living or working space.

  • Precision Fit for Maximum Effectiveness: Engineered with precision, our filters are crafted to fit seamlessly into your HVAC system, with actual dimensions of 20×21.5×4 inches. This precision ensures maximum air circulation, promoting effective filtration throughout every nook and cranny of your indoor environment.
  • Tailored Filtration with Multiple MERV Ratings: Customize your air filtration to meet specific needs with our filters available in various MERV ratings, including 8, 11, and 13. Select the level of filtration that suits your unique requirements, providing you with a personalized approach to achieving a cleaner and healthier indoor atmosphere.
  • Long-Lasting Performance for Extended Comfort: Crafted from durable materials, our 20×21.5×4 air filters are built to withstand the test of time. Experience consistent performance and reliable air purification over an extended period, contributing to a comfortable and healthy indoor environment for you and your loved ones.
  • Effective Filtration Against Airborne Particles: Our filters employ advanced technology to capture a wide range of airborne particles. From dust and pollen to pet dander and mold, our filters work diligently to create an environment where you can breathe easily, free from contaminants that may compromise your well-being.
  • Convenient Online Purchase for Effortless Shopping: Enjoy the convenience of shopping from the comfort of your home. Our user-friendly online platform at Custom Filters Direct allows you to effortlessly browse, select, and purchase 20×21.5×4 air filters with just a few clicks, saving you time and effort throughout the process.


Invest in the well-being of your home or office with Custom Filters Direct. Purchase our 20×21.5×4 air filters online and experience the transformative difference in clean, fresh air for your living or working space.