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MERV 8 Filters Fast® 4" AC and Furnace Air Filters 3-pack


Only $20.32 per Filter
Retail: $70.99 /ea
You Save: 14%
As low as
Retail: $70.99
You Save: 14%
FF4M8 Sizes :
Ships in 1 to 2 business days.
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The Filters Fast® FF4M8 3-Pack is a set of MERV 8 filters that effectively reduces contaminants from your indoor air. Removing these airborne particles can help improve allergies and alleviate sinus irritation that can cause watery eyes, itchy throat, coughing, and sneezing. The MERV 8 filter media is electrostatically charged and constructed with spun micro-fiber that also will not retain moisture, which can lead to microbial growth. Aside from the health benefits, these HVAC filters will also extend the life of your heating and cooling system by making it work more efficiently.

Filters Fast® FF4M8 3-Pack Filter Specifications:

  • Part Number: FF4M8
  • Pack Size: 3 Filters
  • MERV Rating: 8
  • Filter Type: Electrostatic pleated
  • Material: Synthetic
  • Replace every 3 months
  • For commercial and residential use
  • Note: These filters do not contain fiberglass.

The Filters Fast® FF4M8 3-Pack 4" Air Filter is available in the following sizes:

Nominal Size Actual Size Alternate Part Number
12x24x4 Air Filter 11.375x23.375x3.625 PF8.0412243PFF
16x20x4 Air Filter 15.375x19.375x3.625 PF8.0416203PFF
16x25x4 Air Filter 15.375x24.375x3.625 PF8.0416253PFF
18x24x4 Air Filter 17.375x23.375x3.625 PF8.0418243PFF
20x20x4 Air Filter 19.375x19.375x3.625 PF8.0420203PFF
20x24x4 Air Filter 19.375x23.375x3.625 PF8.0420243PFF
20x25x4 Air Filter 19.375x24.375x3.625 PF8.0420253PFF
24x24x4 Air Filter 23.375x23.375x3.625 PF8.0424243PFF
25x29x4 Air Filter 24.375x28.375x3.625 PF8.0425293PFF

NOTE: If you don't see your size, order a custom made air filter! Custom made air filters do not come individually wrapped. Please be advised that some larger filters require an additional cost (see dropdown window above).

Additional Resources:

For more information on air filter efficiency ratings, check out our resources below!

MERV Air Filter Chart

Compatible Models:

The MERV 8 Filters Fast® 4" AC and Furnace Air Filters 3-pack is correct replacement for the following model numbers:

  • GeneralAir TERSus 2000 Air Purification Systems
  • GeneralAire 5FM2025
  • GeneralAire MAC2000
  • Trion 255649-102


Customer Reviews:

Total Reviews: 10 | Average Rating: 4.7 / 5.0

Awesome stuff at awesome prices

Collected by

It fits and it got delivered.

Collected by

Loved it thanks

Collected by

Filter seems to be working just fine. Thanks for the quick service.

Collected by

Fit was perfect and cost was reasonable.

Collected by

Great pet filter!

Collected by

I hope the next time that the HEPA filters gets sent, that they arrive at our address not one where we have to call in and help them find out what in the world happened to our order. They never suggested that it could have been sent to the wrong address, but when I asked them if they checked the address, they said no, checked it and it was the wrong address. Then she stopped pushing me saying that it was already sent to me. We value the products and the savings.

Collected by

Great product, will certainly do more business with this company!

Collected by

Excellent experience filters delivered on time & complete!

Collected by

These work for me, and are a very good value, but be sure they work for you. Actual measurement for the 16 x 25 x 4 filter is 15 1/2 x 24 1/2 x 3 9/16, which makes them very different in size than many other advertised 16 x 26 x 4, which it typically 15 3/4 x 24 3/4 x 4 3/8

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