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12.75x21x1 Air Filter Merv 8
12.75x21x1 AC Filter Merv 11
12.75x21x1 Furnace Filter Merv 13
12.75x21x1 Filter Merv 13 Titanium
12.75x21x1 Filter Merv 10 Carbon
12.75x21x1 Filter Merv 8 Carbon 12.75x21x1 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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12.75x21x1 Air Filter

AC Furnace Air Filter 12.75x21x1 -Inches

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Product Description

Item Model Number: FKFB12.75X21A
Brand: Filter King
Filter size: 12.75x21x1
Actual Size: 12.75 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, 12.75x21x1 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.

12.75x21x1 Air Filter Reviews

What MERV Rating should I choose?

How Often to Change Your 12.75x21x1 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.

12.75x21x1 Air Filter

Filter King 12.75x21x1 size air filters act as necessary tools to protect your home from incoming irritants. The airflow your air systems pump in may contain any number of particles from the outside of your home. The problems with airborne irritants are even worse when it comes to areas with high levels of pollutants or allergens. Air filters are necessary in order to have incoming airflow cleaned so it comes in smelling fresh without issue. However, the air filters in your home will need regular replacement in order to avoid any developing issues with the air systems.

The indoor air quality of your home depends on air filters and their ability to clean up the incoming air flow. The filters themselves consist of a tight mesh weaving that captures particles but allows the airflow to pass without issue. The mesh eventually becomes covered in captured particles and the resulting blockage in an air system only causes more complications over time. A dirty air filter is able to cause indoor air quality to lower, energy billing to rise and increase the strain on your home’s air systems.

The Filter King 12.75x21x1 size filters are capable of fitting into any accompanying air system and providing protection to your home. These filters rate as an eight on the MERV (Minimum Efficiency Reporting Value) scale, which measures the tightness of their mesh weaving. With a rating of eight, the filters are capable of blocking out irritants like:

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

12.75x21x1 Air Filter Delivery

Our delivery services come with discounts that make our already affordable air filters even better choices for home’s on a budget. Orders of two or more filters are shipped for free, and usable upon arrival. We also offer a subscription service that has new air filters delivered monthly. Contact us today and have new filters come in to ensure fresh airflow for your home.