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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. OmniFilter RS12-SS6-05 Polypropylene Sediment Filter

    OmniFilter RS12-SS6-05 Polypropylene Sediment Filter

    Standard 10 inch by 2.5 inch size fits many common filter housings Learn More
    $4.99 Retail Price:  $8.04
  2. RS7-SS OmniFilter Whole House Filter Replacement Cartridge

    RS7-SS OmniFilter Whole House Water Filter Replacement Cartridge

    Fits any brand of whole house water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.38
  3. RS3-SS OmniFilter Whole House Filter Replacement Cartridge

    RS3-SS OmniFilter Replacement 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
  4. 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
  5. RS14-SS OmniFilter Whole House Filter Replacement Cartridge

    RS14-SS OmniFilter Replacement Whole House Water Filter Cartridge

    Fits any brand of whole house water filter system that uses 9 3/4 x 2 1/2 water filter cartridges Learn More
    $6.99 Retail Price:  $9.34
  6. RS14-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    RS14-DS OmniFilter Whole House Water Filter Cartridges (2-Pack)

    Fits any brand of whole house water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.15
  7. 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
  8. 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
  9. CB1 OmniFilter Undersink Filter Replacement Cartridge

    CB1-SS6-S06 OmniFilter Undersink Water Filter Cartridge

    For use in any brand of undersink water filtration systems that use 9 3/4-inch x 2 1/2-inch water filter cartridges Learn More
    $33.99
  10. CB3 OmniFilter Undersink Filter Replacement Cartridge

    CB3-SS6-06 OmniFilter Undersink Filter Replacement Cartridge

    Fits any brand of undersink water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $50.99
  11. 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
  12. GAC1SS OmniFilter Series C Undersink Filter Replacement Cartridge

    GAC1SS OmniFilter Undersink Water Filter Cartridge (Series C)

    Fits any brand of undersink water filtration system that accepts filter cartridges sized 9 3/4 x 2 1/2 Learn More
    $16.99

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