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9.75x23.75x4 Air Filter

Actual Size 9.75 x 23.75 x 3.75-Inches Actual size info The nominal size is the size rounded to the closest whole or half an inch. The actual size is the precise physical size of the filter. Learn more.

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Filter Description

  • Filter size: 9.75x23.75x4
  • Actual Size: 9.75 x 23.75 x 3.75"
  • 4-Inch Thick Filter
  • MERV 8 Filter Rating
  • Protection From: Pollen, Dust, Mold, and Dust Mites.
  • Residential / Commercial Use
DeliveryFree Delivery: Ships in 24 Hours
MADE IN USA

9.75x23.75x4 Air Filter

Actual Size 9.75 x 23.75 x 3.75-Inches Actual size info The nominal size is the size rounded to the closest whole or half an inch. The actual size is the precise physical size of the filter. Learn more.

Filter Quality
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DeliveryFree Delivery: Ships in 24 Hours
30-Day Money-Back Guarantee

If for any reason you are not satisfied with your purchase, return it to us within 30 days, and we'll make it right.

INCLUDED IN YOUR ORDER

  • Made in USA
    Made in USA

    All filters are designed and assembled in the U.S.A.

  • Premium Quality
    Premium Quality

    We design and manufacture our filters right here in the U.S.A.

  • Secure Payments
    Secure Payments

    Your information is always secure and encrypted during checkouts.

What MERV should I choose?

Filter King makes a variety of MERV-rated standard filters for all commercial and residential HVAC systems, and we can also manufacture custom-sized filters on request.

Choose Merv Type

12x24x1 Air Filter

The different sized air filters in your home are essential parts of the system and clean up incoming airflow. The air pumped in by an air system is not always healthy to breathe because of household dust and other irritants, the air surrounding your home is often full of harmful irritants. Filter King 12x24x1 size air filters match the average air system and used to keep incoming airflow from creating any problems with the corresponding HVAC system. The air filters themselves consist of a tight mesh weaving that traps and absorbs passing irritants in the airflow. The filter will continue to clean incoming air flow until the point where it is completely covered in captured particles. A dirty filter becomes a problem in an heating and cooling system, meaning that maintenance becomes necessary before the problems begin to spread.

Air Filter Use for Residential Homes

The average home has its fair share of irritants traveling through the air conditioner systems. Your filters prevent any problems by blocking out household dust, debris, pollutants and allergens alike. Many of the irritants that ride along airflow are harmful to the lungs, the irritants are also able to trigger allergies or other severe reactions. The air filters prevent airborne irritants from spreading but can only do so until they become too dirty to properly work anymore. Dirty air filters still block airborne problems, along with the rest of the air that your home is going to need.

A dirty air filter makes it very difficult for airflow to pass by into the ducts of your home. While irritants cannot pass, the lack of fresh air will become more and more noticeable over time. Your home needs its air cycled before it begins to dry out and stagnate, because old air leads to lower indoor air quality. Fresh air filters let airflow through without an issue and prevent the air quality from lowering, from either stagnation or from intruding irritants.

Air Filter Use for Apartments

When it comes to your apartment it becomes more important than ever to ensure clean airflow because of the limited space. Your apartment air filters will clean out incoming air and prevent the particles already inside from causing further problems. Irritants like smoke particles and pet dander have the tendency to stick to whatever surface they land on whenever they are not cycled out of a room’s air. Your home is much more comfortable when the harmful particles cycle out in airflow, before being trapped and absorbed. The capturing process does not happen as effectively with old, ineffective air filters. New 12x24x1 air filters are clean enough to allow air to cycle while also keeping irritants from passing along to other rooms and continue causing problems.

12x24x1 Furnace Filter

Air filters that work for HVAC systems also fit in furnace systems, cleaning the heated air flow passing by to reach your home ducts. Furnace filters are in between where the air heats up and where the blower fan used to distribute it throughout your home. The air filters become dirtier over time and because the air heats up before filtration this becomes a serious problem. A dirty air filter is a blockage in a system which damaging and dangerous to a furnace when heated air is unable to pass.

When your furnace filters become dirty, then the blockage they create stops air flow from passing through. In other heating and cooling system, a blockage leads to stagnant air and lower indoor air quality, for a furnace the effects are much worse. When air flow is unable to leave the furnace, then the result is an increase in temperatures that the machinery may be unable handle. The furnaces parts may become damaged beyond repair, new parts are costly and unnecessary when a new filter solves the problem at a fraction of the price.

Air Filter Changing Practices

You will need new filters over time to prevent any blockages or issues from developing in an HVAC system. How often your air filters will need replacing is often dependent on your home’s environment and the filters MERV (Minimum Efficiency Reporting Value) rating. Home’s with resident smokers or pets often need air filters to prevent the resulting particles from spreading throughout their rooms. Areas with high levels of pollution or vegetation often require homes with more efficient filters to prevent the spread of harmful irritants, allergens, household dust and mold.

Air filter efficiency ranks on the MERV rating system, its number being the result of various measurements. The tight mesh weaving of your filter ranks on the scale and that ranking shows what particles it is able to capture. Filter King  filters rank as an eight on the MERV scale, which means basic irritants are unable to pass along with other particles including:

  • Pollen
  • Household dust
  • Mold
  • Household dust Mites debris
  • Bacteria
  • Pet Dander
  • Smoke
  • Viruses

Replacing an Old Filter

When you need to install a new filter, then the process only takes a few steps and some time. The location of the air filter is in the air conditioner system owner’s manual, once found and removed you can find the size along the cardboard edge. The new air filter should come in a similar size and from there it is easily installed into the system. The old filter goes into a sealed bag or container to prevent the particles from re-releasing, and you enjoy the resulting fresh, clean air.

Air Filter Delivery

Filter King 12x24x1 size filters provide premium filtration at affordable prices to make maintenance as easy as possible. We deliver your new air filters straight to your front door with our filter change reminder program, orders of two or more filters are even shipped for free! If you need new filters on a consistent schedule, then we offer an air filter subscription service where new filters come as often as by the month. Order today and have your ready-to-use filters arrive in time to ensure you continue breathing fresh, clean air.

FK Lion ALWAYS THE RIGHT FILTER GUARANTEE

Selecting the Appropriate Air Filter Size

Air filters come with both a nominal size and an actual size. The nominal size is typically rounded up to the nearest whole or half inch and is printed in a larger font.

Nominal Size

The nominal size is typically rounded up to the nearest whole or half inch and is printed in a larger font.

9.75x23.75x4

Actual Size 9.75x23.75x3.75

Actual Size

The actual size represents the precise physical dimensions of the filter and is printed in a smaller font.

Nominal Size 9.75x23.75x4
9.75"
Filter Blank
23.75"
3.75"
Actual Size is 9.75x23.75x3.75

Measuring

If your previous filter lacks dimensions printed on the frame,
take a tape measure and record the
length x width x depth.

Key Features

MERV 8 Air Filters stand out as the preferred choice among various MERV ratings. They significantly enhance indoor air quality while optimizing the efficiency of your HVAC system, effectively eliminating up to 90% of airborne contaminants while maintaining optimal airflow.

Industry Standard Board Frames

Paperboard air filter frames are cut to fit any air filtration system, and their purposes is to hold HVAC filters in place. They consist of a weave that traps and absorbs the particles caught in the incoming airflow.

Air Filter

Pleated Air Filters

This innovative design ensures that our filters last three times longer than fiberglass counterparts while effectively capturing harmful particles, ultimately enhancing air quality for everyone.

Protects Against

  • Pollen
    Pollen
  • Dust
    Dust
  • Mold
    Mold
  • Dust Mites
    Dust Mites
  • Bacteria
    Bacteria

Pleated Vs Fiberglass?

A pleated air filter's media follows a folding pattern, which creates increased surface area, and in turn, allows more air flow while maintaining the quality of air. On the other hand, a fiberglass filter has a minimal surface area, and furnace filters out larger particles
like dust and lint and is not very effective.

Pleated Filter
Pleated Filter
  • Larger surface area captures more particles
  • Less replacement frequency
  • Average lifespans of 3-12 months
  • Higher MERV rating 8-13
  • Higher quality, sturdy and durable
Fiberglass Filter
Fiberglass Filter
  • Smaller surface area captures less particles
  • More replacement frequency
  • Average lifespans of 1-2 months
  • Lower MERV rating 2-4
  • Lower quality, flimsy and porous

How often should you change your 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 months without change.

You should change your filter more frequently if you notice:

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

How to install your air filter?

Installation couldn't be easier. Every filter features an airflow arrow printed on its side. It's crucial to align this arrow with the direction of the air when inserting the filter into your furnace or central air return ducts.

  • Step 1
  • Step 2
  • Step 3
  • Step 4

Why replacement Air Filters?

MERV 8 filters stand out as the preferred choice among various MERV ratings. They significantly enhance indoor air quality while optimizing the efficiency of your HVAC system, effectively eliminating up to 90% of airborne contaminants while maintaining optimal airflow.

Clean Air

Clean Air for you and
Your Family

Air filters serve 3 critical roles in your central air system that contribute to the health and comfort of residents and customers. Air filters remove harmful pollen, dust, dander, smoke. and bacteria, so they don't circulate throughout your home or commercial space from a dirty filter.

Clean Air

The comfort of clean air

Air filters serve 3 critical roles in your central air system that contribute to the health and comfort of residents and customers. Air filters remove harmful pollen, dust, dander, smoke. and bacteria, so they don't circulate throughout your home or commercial space from a dirty filter.

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If the measurements on your current filter match the ones mentioned above, then you have identified your filter size.

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About Filter King

Filter King is an air filter manufacturer that specializes in making high quality air filters for a variety of purposes. The company has been in business for over 4 years and has already established a strong reputation for making air filters that are both effective and affordable.

Filter King air filters are designed to remove airborne particles such as dust, pollen, and smoke from the air, making them an ideal choice for people with allergies or respiratory problems. Filter King air filters are used in homes, office buildings, and hospitals across the country.

The company's air filters are also used in a variety of industries, including food processing, pharmaceuticals, and manufacturing. The company offers a wide range of air filters, including models that are custom size, designed exactly for your need.