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OmniFilter K4 Replacement O-Rings for Under Sink


Retail: $10.99 /ea
You Save: 19%
As low as
Retail: $10.99
You Save: 19%
in stock
Ships by Monday 1/24/2022
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The OmniFilter K4 Replacement O-rings pack contains the following four o-rings:

  • 1 Blue K4: fits OB3, SFM2 Series A, CBF1, CBF3 Series A, OT32 Series A, RO2000, R14, CBF20 and OB1.
  • 1 Black WC9-13: fits white-head OB5 and OCT2.
  • 1 Black OK40: fits OB1 Series A, OB5 Series A, R12 Series A and U25 Series E.
  • 1 Black OK30: fits CBF1 Series A, CBF3 Series B, OT32 Series B, SFM2 Series B, RO2000 Series B

Because OmniFilter has updated their housing designs, they are selling this kit with o-rings that fit the new and old systems to ensure customers get the correct o-ring for their system. This is why the K4 is listed as fitting the same housings as the OK30, for instance.

OmniFilter does not sell the K4 separately.

These o-rings come in the following dimensions:

  • 1 Blue for Undersink Filter Systems: 3-1/2 inches (ID) X 3-3/4 inches (OD)
  • 1 Black for Medium Duty Whole House Systems: 4-7/8 inches (ID) X 5-1/8 inches (OD)
  • 2 Black for Medium Duty Whole House Systems: 3-7/16 inches (ID) X 3-5/8 inches (OD)

This product was known previously as model number K4-R-02 and is now known by model number K4-M6-05.

Compatible Models:

The OmniFilter K4 Replacement O-Rings for Under Sink is correct replacement for the following model numbers:

  • CBF1 Series A
  • CBF3 Series A
  • CBF3 Series B
  • OB1 Series A
  • OB5 Series A
  • OT32 Series A
  • OT32 Series B
  • R12 Series A
  • RO2000
  • RO2000 Series B
  • Series A
  • SFM2 Series B
  • U25 Series E
  • white-head OB5 and OCT2

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