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BestAir 20 in. W X 20 in. H X 4 in. 8 MERV Pleated Air Filter

BestAir 20 in. W X 20 in. H X 4 in. 8 MERV Pleated Air Filter

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

MERV 8 pleated filtration that traps dust, pollen, smoke, mold spores, bacteria, and viruses without restricting airflow.
Bestair MPN BA4-2020-8 In Stock & Ready to Ship
$44.97
$14.99 each · sold by the case of 3 Free shipping on orders over $149
Ships within 24 hours · most orders arrive in about 2 business days
Cases of 3 · Order in multiples of 3
Ships free on orders over $149 $14.99 flat shipping until your order reaches $149.

Sold by the Case

$44.97 per case of 3

Save $6.75 on orders $75+. Spend $75 or more to unlock 15% off every case — applied automatically at checkout. Free shipping at $149.

Ships as a complete case of 3. Free shipping on orders $149 and up.

About Product Overview

This BestAir 20x20x4 pleated furnace filter is built for whole-house filtration, catching everyday airborne irritants before they cycle back through your vents. With a MERV 8 rating, it's a solid step up from basic fiberglass filters, trapping dust, lint, pollen, mold spores, smoke, and even bacteria and viruses. The pleated design gives it more surface area to work with, so it filters efficiently without choking airflow. Made in the USA and sized to fit standard 20x20x4 furnace and HVAC systems, this filter is not trimmable, so double-check your housing before ordering.

  • Nominal size: 20 x 20 x 4 inches
  • Actual size: 19-1/2 x 19-1/2 x 3-3/4 inches
  • MERV 8 rating for high-efficiency filtration
  • Filters dust, lint, pollen, mold spores, smoke, bacteria, and viruses
  • Pleated construction, not trimmable
  • Made in USA; sold individually

The Details Specifications

Brand Bestair
Model / MPN BA4-2020-8
UPC 078757017909
Weight 5 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
Price check

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On Amazon, start with these four questions before you click buy.

01

Who's actually selling it

The brand name is on the listing. A different company is in the seller field. Those aren't the same thing, and the second one is who you're buying from.

02

Whether the warranty survives

Most manufacturers only honor a warranty when the unit came through an authorized dealer. We're authorized for Bestair. A third-party marketplace seller usually isn't.

03

Where the box came from

Gray-market stock, returns repackaged as new, and outright fakes move through marketplaces constantly. It all looks identical in the photo. It stops looking identical when it fails.

04

Who you call when it breaks

Ours is a phone number with a person behind it who has held this product. M–F, 6 AM – 5 PM Pacific. (866) 469-8556

The big boxes don't care if your hardware store survives.

Amazon, Home Depot, and Lowe's are built to pull every hardware dollar out of your town. When the local shop can't keep the lights on, the counter where somebody actually knew which part you needed goes with it. We're built the other way: real brands so you're never stuck on a marketplace, and a straight answer to buy it down the street when that's the better call. Support independent hardware — it doesn't restock itself.

Why we tell you to shop local
Authorized dealer · Bestair

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