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13x21x1 Air Filter Merv 8
13x21x1 AC Filter Merv 11
13x21x1 Furnace Filter Merv 13
13x21x1 Filter Merv 13 Titanium
13x21x1 Filter Merv 10 Carbon
13x21x1 Filter Merv 8 Carbon 13x21x1 Filter Merv 8 Carbon
Protects All Against
  • Pollen protection
  • Dust protection
  • Mold protection
  • Dust Mites protection
    Dust Mites
  • Bacteria protection
  • Pet Dander protection
    Pet Dander
  • Smoke protection
  • Viruses protection
  • Cooking Smoke protection
  • Odor protection
  • Smog protection
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13x21x1 Air Filter

AC Furnace Air Filter 13x21x1 -Inches

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Odor Eliminator

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Product Description

Item Model Number: FKFB13X21A
Brand: Filter King
Filter size: 13x21x1
Actual Size: 13 x 21 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

Why Buy Air Filters From Filter King?


In comparison to fiberglass filters, 13x21x1 pleated air filters are at least 20 times more effective. All Filter King air filters are made in the US.


Filters frames are made out of heat resistant paperboard with horizontal grid supports. Able to withstand temperatures of up to 200° F and resistant to moisture, the paperboard frames do not support microbial growth and outperforms traditional cardboard frames.


Chemical free, electrostatically charged synthetic polyester media is pleated, maximizing the surface area, to capture a high number of airborne particles as small as 0.3 microns with low air flow resistance. To increase durability, the media is supported with a corrosion resistant steel wire.

13x21x1 Air Filter Reviews

What MERV Rating should I choose?

How Often to Change Your 13x21x1 Air Filter?

Filter King AC & furnace filters aren’t the typical fiberglass filters that need to be replaced every 30 days. Our filters can typically be used for 3 to 5 months before requiring to be changed. Naturally, a variety of things influence filter lifespan.

Some of the factors that influence your filter’s life include outdoor air quality, whether pets are in the home, and how well your HVAC system is maintained.

Your air filter becomes clogged over time by trapped particles, preventing airflow. The efficiency of the HVAC filter declines. Your system must work harder to heat and cool your home. The extra strain on the HVAC system causes higher energy bills. Regular home air filter replacements can prevent expensive system repairs or replacements down the road.

You should change your filter more frequently if you notice:

  • Household dust build-up
  • The air isn’t cooling as is used to
  • There’s more dust near the air vents
  • A dirty filter surface
  • Higher energy bills
  • Burning smells near your HVAC system.

13x21x1 Air Filter

Filter King 13x21x1 size air filters are used by your air systems to clean up the incoming airflow pumped in from outside. The air coming into your home may not be the cleanest, and without filtration your air systems have no way of ensuring the air coming in is safe. Your air filters will be able to clean up incoming airflow by trapping and absorbing incoming irritants inside their tight mesh weaving. The indoor air quality of your home benefits from the clean airflow, but the filters are not capable of remaining effective forever.

Your air filters are capable of trapping harmful irritants for as long as they mesh weaving is capable of stopping them. Eventually, the weaving becomes so full of irritants that the airflow coming into your home is hindered or stopped entirely. A home without airflow sees its air stagnate and dry out, which is both uncomfortable and unhealthy to breathe in. Your home air systems will also begin using more energy, which becomes a burden on billing and creates mechanical strain for a system.

You will need to replace the air filters in your home with new ones to avoid complications throughout your systems from becoming worse. We offer 13x21x1 size air filters that are available for easy installation into accompanying air systems. Once installed, the filters are capable of effectively cleaning out airflow, they have a MERV (Minimum Efficiency Reporting Value) rating of eight. The MERV rating of a filter is the measured efficiency of its mesh weaving, our filters are capable of blocking out irritants like:

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

13x21x1 Air Filter Delivery

The air filters in your home will need replacement on a regular schedule to avoid the complications resulting from the possible blockage. We offer 13x21x1 size air filters at affordable rates that regular replacement easier for the average home. Our quality delivery services have your filters delivered straight to you, we also have a subscription option to have new filters shipped as often as monthly. Bulk orders have additional benefits, we even ship orders of two or more filters for free! Order now and help ensure that the airflow for your home is coming in clean.