• 21x23x1 MERV-11 Air Furnace Filter
    • 21x23x1 MERV-11 Air Furnace Filter

    21x23x1 MERV-11 Air Furnace Filter

    Everyone else: $ 14.99"Everyone else" is defined as OEM (Original Equipment Manufacturer). Why pay the big brands prices when you can pay less? $ 10.99 & Free Shipping!

    This single replacement furnace filter will keep your nose and lungs from getting clogged up with gunk. It's got a MERV 11 rating, making it one of the best residential filters you can purchase. That MERV 11 rating means that the filter will remove over 95 percent of debris and particulates that are 1 to 3 microns or larger. That includes the standard stuff like dust mites, pollen, mold spores, and pet dander. It also includes things you wouldn't think about like flour, pudding mix, and hair spray particles. You might not ever really need your filter to take care of those things, but just in case, there it is. Just remember to change your filter every three months (or sooner) to maintain maximum efficiency.


      Approximate dimensions:

      • 21" x 23" x 1"

      When will my order ship?

      Our warehouse ships Monday-Friday. If you place your order before 12pm EST, your order will ship out that same day. Orders placed after 12pm EST will ship the following weekday.

      What is your return policy?

      We want you to love what your ordered and we are confident that our products and service will help you live a healthier life. If something isn't right give us a call at 877.750.9239, 9am - 5pm (EST) Monday - Friday, or email us at If you are not 100% satisfied with your purchase, you can return it for a full refund (returns must be unused, in original packaging and within 30 days of your order date).

      How can I track my order?

      Thank you for your recent purchase with Think Crucial. When your order ships, you should receive an email with your tracking information. Please check your spam folder if you have not received it. Please feel free to contact us for further information regarding your order. Most of our packages are shipped using DHL Global Mail. DHL Global Mail's tracking information usually start with 92 and include 26 numbers. Our international orders are also shipped using DHL Global Mail, tracking numbers starting with GM. DHL Global Mail packages are transferred to USPS for the final mile delivery. Click here to for up-to-date information regarding your package's location. We also use USPS, UPS and Fedex to ship out our orders. Tracking information can be found on each companies respective website.
      - USPS's tracking number usually starts with 94 and include 22 numbers.
      - UPS tracking numbers usually start with 1Z and continue with 15 additional numbers.
      - Fedex tracking numbers start with either 61 and include 20 numbers or 59 and include 15 numbers.

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