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Filter King

Filter King 21.5x21.5x1 Air Filter | 4-PACK | MERV 8 HVAC Pleated A/C Furnace Filters | MADE IN USA | Actual Size: 21.5 x 21.5 x .75"

  • Based on 3,886 reviews
Condition: New
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To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

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Availability: In Stock.
Fulfilled by Filter King LLC
Arrives Oct 8 – Oct 9
Order within 23 hours and 13 minutes
Available payment plans shown during checkout

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Size: 21.5x21.5x1


Features

  • FILTER: This is a MERV 8 rated 4 pack Air Conditioner Filter | Size: 21.5" x 21.5" x 1" - Actual Size: 21.5" x 21.5" x .75"
  • MADE IN USA: Fully manufactured in the United States. Made from the highest quality materials and construction. (EPA Establishment Number: 103501-FL-1)
  • MAX PERFORMANCE: Our filters can last up to 90 DAYS before needing replacement. We do recommend to change your home air filter every 30 - 90 days for 1 inch filters. This will help maintain the longevity of the intended application like A/C and heaters
  • CAPTURE MORE: Protect your home! The pleated design captures more particles and extends lifetime of the filter. Merv Filters trap airborne particles without impacting air flow. Feel the difference in 48 hours.
  • FAST & EASY INSTALLATION: Open, Slide and Close! A simple yet effective replacement air filter for your home.

Brand: Filter King


Material: Paper


Product Dimensions: 21.5"L x 21.5"W x 0.75"Th


MERV Rating: 8


Compatible Devices: Air Conditioner, Furnace


Global Trade Identification Number: 91, 80


Number of Items: 4


Manufacturer: Filter King


Product Grade: 5


Unit Count: 4.0 Count


Brand Name: ‎Filter King


Model Info: ‎FK21.5x21.5x1A-M8


Item Weight: ‎5 pounds


Product Dimensions: ‎21.5 x 21.5 x 0.75 inches


Item model number: ‎FK21.5x21.5x1A-M8


Part Number: ‎FK21.5x21.5x1A-M8


Special Features: ‎Easy to Install


Compatible Device: ‎Air Conditioner, Furnace


Material Type: ‎Paper


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: November 15, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Oct 8 – Oct 9

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Rift size
Size: 19.5x19.5x1 Inch (Pack of 4)
Fit perfectly and good sturdy product.
Reviewed in the United States on July 21, 2025 by Rita B
    • The filters are the correct size for my system.
Size: 11.5x11.5x1 Inch (Pack of 4)
They had hard to find, older sized filters. Much cheaper than going to 3 or more stores just to get what is needed. This purchase will service my AC for a full year.
Reviewed in the United States on August 6, 2025 by Michael
    • Excellent, high quality filters. Clear dust and other particles and trap them in place.
Size: 19.5x19.5x1 Inch (Pack of 4)
Excellent, high quality filters. Clear dust and other particles and trap them in place.
Reviewed in the United States on July 26, 2025 by Mark J. Occhipinti
    • Decent replacement filter.
Size: 9x11x1
Got it quick in decent packaging. Not sure why the paper frame has cross-crossing supports when the pleats are supported by wire mesh, but it works fine. The filter dimensions are small enough that the wire mesh is sufficient and the cross-crosses block air.
Reviewed in the United States on April 29, 2025 by KCCjr
    • Good price, good quality
Size: 16x21x1
Quality product for purifying the air.
Reviewed in the United States on July 23, 2025 by Judy Cunningham
    • Odd size. No problem!
Size: 15.5x24.5x1
Perfect fit. It was just the size I needed.
Reviewed in the United States on July 27, 2025 by Amazon Customer
    • Filters that fit!
Size: 15.5x19.5x1
I was having difficulty finding filters to fit my furnace. These worked well!
Reviewed in the United States on July 31, 2025 by Lorraine T.
    • Great quality and price!
Size: 22x22x1
Second time I’ve ordered them. Outstanding quality and great price.
Reviewed in the United States on July 15, 2025 by Linda Baker

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