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Replacement Water Filters: Undersink

Don’t settle for a replacement under sink water filter cartridge that simply fits, find one designed and manufactured specifically for your under sink water filter system.

Discount Filter Store has one of the largest selections of undersink filter cartridges. With under sink filter cartridges available in over 15+ different filter medias, 8+ different sizes (5x2½ - 20x4½), and a wide variety of filter life’s ranging from 250 gallons to 50,000+ gallons, you’re guaranteed to find the under sink water filter system and/or replacement cartridges you need. Choose from hundreds of under sink water filter cartridges from some of the industry’s top brands including American Plumber, Crystal Quest, Pentek®, Culligan®, GE, Aqua-Pure®, Whirlpool®, and more.

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  1. EP-5 Pentek Replacement Filter Cartridge

    EP-5 Pentek Replacement Filter Cartridge

    Fits most housings that accept standard 5-inch x 2.5-inch water filter cartridges Learn More
  2. RS2-SS OmniFilter Whole House Filter Replacement Cartridge

    RS2-SS OmniFilter Whole House Water Filter Cartridge

    Fits any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.04
  3. TO1SS OmniFilter Whole House Filter Replacement Cartridge

    TO1SS OmniFilter Whole House Water Filter Replacement Cartridge

    Designed to fit into any brand of whole house water filtration system that accepts standard 9 3/4 x 2 1/2 inch cartridges Learn More
    $12.99 Retail Price:  $15.34
  4. TO6 OmniFilter Whole House Filter Replacement Cartridge

    TO6-SS2-S06 OmniFilter Whole House Water Filter Replacement Cartridge

    Fits into any brand of whole house water filtration system that accepts filter cartridges sized 9 3/4 x 4 1/2 inches Learn More
    $22.99 Retail Price:  $24.14
  5. RS4-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    RS4-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    Fits any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
  6. W5CIP American Plumber Undersink Filter Replacement Cartridge (2-Pack)

    W5CIP American Plumber Undersink Filter Replacement Cartridge (2-Pack)

    Fits American Plumber W38-PR and most standard size water filter housings Learn More
    $21.99 Retail Price:  $24.34

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