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21.25×21.25×1 – Merv 11

21.25×21.25×1 – Merv 11
AC Furnace Air Filter
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2 $0.00
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4-5 $0.00
6-11 $0.00
12+ $0.00

Product Description

Filter Size: 21.25×21.25x1A

Actual Size: 21.25×21.25×1

Actual Size Fraction : 21-1/4×21-1/4×1

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Order 21.25×21.25×1 Air Filters Delivery

As more people become sensitive to exposure to mold and pesticides, it’s becoming more important for homeowners to maintain indoor air quality by using an air filter. Custom Filters Direct 21.25×21.25×1 air filters can help remove particulates from the air before they reach your lungs, so you’re better protected against inhaling allergens. They can also help reduce the number of airborne bacteria. This can help reduce the risk of getting sick from exposure to harmful bacteria.

These AC and furnace air filters come with a unique design, offering superior filtration to address today’s indoor air quality problems. Manufactured in the USA in our own factory, our filters come with tight mesh weaving to capture small size particles.

However, every air filter needs a replacement after a few months. If you don’t regularly clean your filter, you will end up with mold growth and possibly even a musty smell. A good rule of thumb is to place a new filter in your HVAC unit once every three months. This will not only provide a higher level of filtration but also make your HVAC unit perform efficiently.

Select the Right MERV Rating


These air filters are an effective solution to improve the indoor air quality of your home as they filter out 85% of the airborne allergens 3-10 microns in size.


These AC and furnace air filters are designed to fit both commercial and residential environments. MERV 11 filters capture more than 85% of particles ranging between 3-10 microns in size and 50% of the particles 1.0-3.0 microns in size.


MERV 13 filters eliminate more than 90% of harmful pollutants ranging between 3-10 microns in size and 75% of the particles 0.3-1.0 microns in size. These filters are ideal for industrial, commercial, and residential settings where superior air filtration is required.

21.25×21.25×1 Air Filters Delivery Service

Enhance the indoor air quality by choosing Custom Filters Direct 21.25×21.25×1 air filter. We offer a subscription service, so you can enjoy our best pricing on 21.25×21.25×1 HVAC air filters that are delivered to your door on a monthly basis. You only need to choose the time gap between the deliveries and we will take care of the rest. We can also offer the one-time delivery option. Place your order now!