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Captain O-Ring - K4 Replacement O-Ring Kit for OmniFilter K4, CBF1, CBF3, SFM2, U30, USM2, OT32, RO2000, RO2050, and More (2 Sets, 8 Orings)

4.8 (8) Write Review
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$11.59

$ 5 .99 $5.99

In Stock

About this item

  • The Replacement OmniFilter K4 O-Ring Kit (also called K4-4PAK, K4-R, K4-04, K4-DC6-S18) contains 4 different o-ring sizes to fix your leaking water system.
  • This convenient 2 set package contains 2 of each size, for 8 o-ring gasket seals total.
  • Compatible with: OmniFilter CBF1, CBF3 Series A, CBF20, OB3, OB5, OT32 Series A, Omni Super, Omni Deluxe, Omni Regular, OT5, RO2000, ROT2000-TDS, R12, R14, SFM2 Series A, Total 2, Total Plus, UC2, U30, U400, U450, U500, U600, U700; Culligan US-316; DuPont WFDW12009W, WFDW12000, WFDW13000, WFCH1; and Falsken Heater Treater [FAL-OR-KIT / The Heater Treater 10/20 Replacement O-Ring Kit].
  • Molded from NSF 61 certified buna-n rubber for safe and clean drinking water.
  • Manufactured and warrantied by Captain O-Ring LLC. Proudly assembled in the USA!


Product Description

The OmniFilter K4 Replacement O-Ring Kit (also called K4-4PAK, K4-R, K4-04, K4-DC6-S18) contains 4 different o-ring sizes. This convenient 2 set package contains 2 of each size, for 8 o-rings total.

Compatible with:

  • OmniFilter CBF1, CBF3 Series A, CBF20, OB3, OB5, OT32 Series A, Omni Super, Omni Deluxe, Omni Regular, OT5, RO2000, ROT2000-TDS, R12, R14, SFM2 Series A, Total 2, Total Plus, UC2, U30, U400, U450, U500, U600, U700
  • Culligan US-316
  • DuPont WFDW12009W, WFDW12000, WFDW13000, WFCH1
  • Falsken Heater Treater [O-Ring Kit Part Number: FAL-OR-KIT / "The Heater Treater 10/20 Replacement O-Ring Kit", includes both the smaller slimline size and the larger standard size]

What to expect: This item includes eight (8) o-rings (4 sizes, 2 of each size) in a resealable zip-top poly bag with "Captain O-Ring" branded packaging.

Manufactured and warrantied by Captain O-Ring LLC. Proudly assembled in the USA!

Includes four (4) different o-ring sizes. Two (2) of each size. Eight (8) o-rings total.

3.86

3.86" Inside Diameter x 0.14" Thick

3.48

3.48" Inside Diameter x 0.14" Thick

3.36

3.36" Inside Diameter x 0.14" Thick

3.28

3.28" Inside Diameter x 0.10" Thick


P. Souza
Reviewed in the United States on September 28, 2024
These fit my under cabinet water filter perfectly. No issues.
Eric in Cincinnati
Reviewed in the United States on September 13, 2024
The 4 options are good, but it did not fit my older filter.... Good news, the seller did allow returns...
Angela L.
Reviewed in the United States on March 26, 2024
It was a good price but I feel.it should have been included with the order of the filters
nelson king
Reviewed in the United States on October 14, 2024
Great assortment of o-rings for whole house water filter. Works great.
Janice Wisinski
Reviewed in the United States on January 15, 2024
These O-Rings are for my under-the-sink water purifier. The package comes with different sizes to fit many types of filters.
Kent W.
Reviewed in the United States on September 11, 2021
Should send it back as it is a 2nd rate after market product.....made to look as if it was from Omnifilter.....2 of the o rings won't even work
Susan Joseph
Reviewed in the United States on December 24, 2021
This product didn't work for us. Because it was too thin it didn't stop the leak.
Bob Lablaw
Reviewed in the United States on March 9, 2020
I did not realize there were two different sizes in the package. First one I pulled out was too small and I was not happy. Then when I was putting it back in the bag is when I saw the two different sizes. The next one I tried worked perfectly.