• 20x20x4 AIRx ALLERGY TopTech TT-FM-2020 Replacement Air Filter - MERV 11, 2-Pack

20x20x4 AIRx ALLERGY TopTech TT-FM-2020 Replacement Air Filter - MERV 11, 2-Pack

Model: 20x20x4TT-ALLERGY / Part: #177889
5
125 review(s)
◆
 
Average rating 4.8/5
5 stars
(108)
4 stars
(9)
3 stars
(5)
2 stars
(1)
1 star
(2)
  •  Free Returns
  •  100% Compatibility Guarantee
20" X 20" X 4" Replacement For TopTech TT-FM-2020
TOTAL $88.27 ( 2 Pack for $0.00 each )

In Stock

2026-04-06

Is this the right air filter for you?

If you want superior indoor air quality (IAQ) for your family, this filter is for you!    This filter removes many allergy-causing pollutants like pollen and dust mite debris and keeps your air clean.   We promise convenient ordering and complete satisfaction!

  • Quality 4" pleated air filter offers improved filtration and longer service life over common 1" filters 
  • MERV 11 rating means the filter attracts and holds household allergens like dust, pollen, mold spores, and other small particles that irriate your lungs
  • Replaces the TopTech TT-FM-2020 filter - nominal size 20x20x4 (actual size 19-3/8" x 19-3/8" x 3-5/8")
  • Will also replce the new TopTech "QwikBox" filter, part number TT-FM-2020QB
  • Replace every 6 months under normal use
  • Made with pride in the USA
  • Fast Shipping and Free Returns on all filters

What does this air filter remove?

What part numbers does this filter replace?

  • Toptech TT-FM-2020, TT-FM-2020QB

What air cleaners does this filter fit?

  • TopTech TT-MAC-2020, TT-MAC-2122
Do you want to know about the technical specs?

Nominal Dimensions 20 x 20 x 4"
Actual Dimensions 19-3/8" x 19-3/8" x 3 -5/8"
Filter Media Electrostatically charged 100% synthetic gradient media that does not support microbiological growth
Filter Support Grid 30 gauge galvanized expanded metal grid
Frame Moisture resistant double-wall beverage board
Max Temperature 180F (82C) continuous service, peak 225F (107C)
Max Humidity Resistant to 100% R.H.

Reviews

5
4.8 / 5 (125)
Judith Durant 4 days ago
5
Super helpful with pets!
George Davis 29 days ago
5
received on time and fits the furnace
James McCaffrey 11 days ago
5
I initially bought filters at Lowe's and they did not fit so I got them through this site and I love them and they were a lot cheaper.
Robert Schoales 27 days ago
5
Excellent product and customer service
Mary Pergande 27 days ago
5
Filter works wonderfully. Better yet is DiscountFilters.com customer service!
Mike Weaver 27 days ago
5
This product works great in our home. Seasonal allergies are tough in Indiana and we have two Golden Retreivers in our home
Leslie Cummins 9 days ago
5
So glad we have some where that we can purchase our filters at a discounted rate. Our filters for our home are very expensive and would not be able to change them as often as we avoid. But since we found discount filters we can do the most healthy and change more often. Thank you
Faith Dulaney 10 days ago
5
works fine
David Hammons 18 days ago
5
As advertised
Charles E Blakeman 27 days ago
5
Good product and service with competitive prices.
Farhad Farzaneh 10 days ago
5
Goog quality filters
Robert T Shebert 15 days ago
5
Economical and equivalent quality to the factory-installed product!
David Cuttino 0 day ago
5
Works well.
Frank Gable 10 days ago
4
seems to fit well into the AC apparatus.
Linda E Roy 10 days ago
5
Box came in damaged and hoping the crinkle in the Filter won't hinder sliding into the opening the filter goes in...
Bonnie Post 20 days ago
5
Delivery so fast and good price.
Melinda Johnson 3 days ago
5
It only needs to be changed every 5-6 months.
Melinda Johnson 12 days ago
5
It is a great filter & the price is good, too!
Robert Murray 29 days ago
5
Great filter that is always delivered in a timely manner.
Jack Keesing 8 days ago
5
They were bought for future replacement of current filters, Will know in 6 months how they worked out.
Andrew Finlayson 16 days ago
3
Poorly assembled and poorly packed. Filters slightly damaged in shipping.
Clay Kallman 8 days ago
5
My product showed up on time and works very well. Thanks.
GV 22 days ago
5
Very cost effective ang very good quality
Frank Irizarry 18 days ago
5
excellent product and service
Farhad Farzaneh 16 days ago
5
I like the product very much, both quality and price
Jesus Resto 29 days ago
5
Great customer service and communication as always. Definitely cheaper than local hardware stores.
Kevin Donegan 28 days ago
5
Seems to be an excellent replacement. Very satisfied
Jacqueline Cobb 19 days ago
5
First item arrived damage in shipping and I jumped online and spoke with one of your amazing reps and within a few minutes I had replacements on their way…you guys truly have the customer service down to a science….a true pleasure doing business with a company that values their customers.
Wilson Herme 25 days ago
5
Fits perfectly!!
Farhad Farzaneh 28 days ago
5
was on time
Frank Irizarry 7 days ago
5
Order received ahead of schedule. Thank you
Becky Pugmire 16 days ago
5
I have used Discount filters for several years and I have never been disappointed! Their products are 1st class and the service is the best! Thank you Discount Filters.
GINGER CLAMPIT 25 days ago
5
Receive in timely manner.
Melinda Johnson 28 days ago
5
These filters were a good value for the money & delivered in a timely fashion!
Norma Perry 5 days ago
5
I’m really glad to know who to contact the next time I need more! tks
Jack Null 12 days ago
5
seems to be a great filter will order again
Mary Anne 30 days ago
5
Great service- accurate and speedy
Jim Yauger 6 days ago
5
A little high priced but excellent service snd good product
Denmark Betty 11 days ago
5
Same filter we order from service tech!
Kimberly Bullers 16 days ago
5
These filters are great, but they are a little pricey. Best to buy them at Discount Filters! Outstanding service. Always a coupon available.
Sheldon Pine 28 days ago
5
Good product, easy to install, good value
Melinda Johnson 14 days ago
5
It was what I was looking for & even better that I didn’t have to assemble it.
Lawrence Davis 14 days ago
5
The filters keep our air very clean at a reasonable price. They are half the cost of the ones that our HVAC service people provide.
Dora L 21 days ago
5
Website easy to use, quick shipping. For quality, this is the first time ordering this replacement filter for Top Tech filter and just installed, so I have to see how it holds up. Will be ordering again.
Chuck 1 day ago
4
expensive. I got what I ordered quickly
Tim Meister 21 days ago
5
Great filters. Price is fair for such good quality and you get them quick.
Allen Fletcher 23 days ago
5
The product exceeded expectations it was shipped and received on time.
Richard Lyles 1 day ago
5
The product is outstanding and I will order again.
David Thompson 1 day ago
5
This product is of highest quality, reasonably priced and I receive extremely prompt service. Could not be more pleased. That’s why I continue reordering with this company.
Becky Pugmire 1 day ago
5
Saving money and protecting my environment and furnace by changing filters myself.
Katherine LaBarca 16 days ago
5
I was happy to find these. The A/C company wanted $250 to come out and swap the filters. Took me a few minutes and I never did this before. Fit perfectly.
Sara T 21 days ago
5
Took a while to ship but worth it for the price.
Valerie Farmer 19 days ago
5
Fits my unit perfect.
Steve D 21 days ago
5
Good product and price, fast delivery.
Bill Kleckner 21 days ago
5
Great product at very good price with fast delivery! Highly recommend this company. I will be a returning customer.
Edwin 24 days ago
5
I order 4 changes each year. They always come when I need them. They are a great filter.
Paul G 24 days ago
5
The air filters ingest from discount filters are top quality for a great price.
Robert Murray 30 days ago
5
Very good Filter at a very good price. Highly satisfied with the service given by Discount Filters.
Harry 17 days ago
5
I have been buying there for years
George Gerberick 27 days ago
5
Prompt service, great product.
Tim T 13 days ago
5
Direct replacement at a good price.
Leslie A. Cummins 23 days ago
5
I purchased the wrong filter. When I called in the sales girl was so helpful and nice.
Maureen Neilson 1 day ago
5
Filters are perfect fit . Free delivery, great. Timely delivered. I’ll use this website again and recommend it.
Timothy Thibodeaux 25 days ago
5
The filters are of good quality and delivered on time.
Juanita Mowery 9 days ago
5
Not only the quality of the filter, but the good service you give!
Janice Weaver 26 days ago
4
So far good product I have used for four years the only way it would be better would be free
Michael Bruno 0 day ago
4
Too early to tell how the quality will work. Just installed it. We'll know after 3 to 4 months if it performs up to original quality. Will let you know.
Patricia 13 days ago
5
We use this product faithfully and it's the exact same filter the A/C company uses!! Much less expensive, though!!!
Robert 28 days ago
5
A good value for the money.
Edward Cohen 3 days ago
5
Excellent product- delivered in a couple of days.ready to use!
CHARLES G HOWARD 12 days ago
5
PRODUCT AS ADVERTISED QUICK SHIP
David Troy Smallwood 16 days ago
4
LOWERED MY ELECTRIC BILL AFTER SWITCHING TO MERV-11 FILTERS. COST PER FILTER IS A LITTLE HIGH.
KIM L MAY 14 days ago
4
Solid filter, not flimsy. No assembly necessary
Jeffrey Stultz 14 days ago
5
This was a very difficult product to find in the stores. I was able to order a two pack on-line for a much more reasonable price than trying to drive and find one all over town. Lowe’s has a filter that was the correct specs but did not fit my system, and it was more expensive. I am very happy with my purchase!
David Cuttino 25 days ago
5
Easy ordering, quick shipping, better air quality, good value! Thanks
William Barclay 2 days ago
5
easy to order replacement filter great price.
Darren Alderman 19 days ago
5
Perfect fit!
Doug Meyerhoff 12 days ago
5
Been offering these same filters for 6 years now! Wouldn’t buy them anywhere else.
Faith Dulaney 14 days ago
5
1/3 the price of what I’d been paying locally-same great product
Willie Poindexter 19 days ago
5
So far so good. They seem to be quality filters at affordable prices.
Tammy Erwin 26 days ago
5
Great filter at a reasonable price. Arrived within a few days. Thank you.
Sherri Hawkins 25 days ago
4
Seems to do the job. Sensor light is off.
Lana Wade 3 days ago
5
Received filters in timely matter and they fit perfect.
Stephen F Tucker 17 days ago
5
I haven't used them yet but the past filters are top notch, fit very well
Edward Cohen 27 days ago
5
Very good product, price is right on point
Robert Curtis 28 days ago
5
Excellent product, fits perfectly and has performed well so far. Delivered when promised, and the price was spot on.
Manuel Negron 9 days ago
5
Great replacement product
Ken Muldowney 14 days ago
3
A middle of road product does not seem very sturdy or durable. Would not purchase this again
Paul Perez 20 days ago
5
It worked well and was priced fairly.
Douglas Woodward 10 days ago
5
Its very simple, my AC guy wanted over $100.00 to come and install a new #11 (same as this one) filter and I got them under $25.00. The istall took 10 mins total. I will be back next time ( a year) for my next one! Doug
Juanita Mowery 23 days ago
5
This was my 2nd or 3rd order, very efficient in delivery. I couldn't find this size in stores in my area! Thank you so much!
Edward Cohen 23 days ago
5
Product is as good as original Top Tech filter.Very pleased with quality, price and they came within a few days.
Douglas Woodward 20 days ago
5
I got 2 for less than I had been paying for one and installation was not hard!
Daryl Woodhouse 2 days ago
5
Excellent filter! It really cuts down on the dust!
Tim Meister 1 day ago
5
Couldn't find filter at box store. They had it at a great price, got to me quickly, free shipping. Makes life easier!
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Replaces These Filters:

National Filter Sales:
20x20x4
PF-02-202004TT-2
TopTech:
TT-FM-2020
TT-FM-2020QB

Fits In These Systems:

TopTech:
TT-MAC-2020
TT-MAC-2122

No Instructions Yet.