Cart 0
dupont ispring apec filtro de agua culligan systems aquasana water purifier whole house water filter whole house water filter system aquasana filter replacement cartridge well water Plomero plumber contractor purificador de agua toda la casa agua de pozo Water filtrations system with UV sterilizer Plumber Plomero Ultraviolet Sterilizer Ballast, Bluonics UV light REverse osmosis
dupont ispring apec filtro de agua culligan systems aquasana water purifier whole house water filter whole house water filter system aquasana filter replacement cartridge well water Plomero plumber contractor purificador de agua toda la casa agua de pozo Water filtrations system with UV sterilizer Plumber Plomero Ultraviolet Sterilizer Ballast, Bluonics UV light REverse osmosis

Bluonics Big Blue Replacement 4.5" O–Ring Black

✔ Trusted by 200,000+ U.S. homeowners
✔ Over 10 years of proven water filtration experience

WH-ORING-PART
Replacement O–Ring for Bluonics Big Blue Whole House and Well Water Filter  4.5"x 10" and 4.5"x 20" and Triple Big Blue units
The Bluonics Big Blue Replacement 4.5" O–Ring Black is a sensational customer favorite, and we hope you like it just as much.

Inventory Last Updated: Jun 12, 2026

Customer Reviews

Based on 9 reviews
67%
(6)
22%
(2)
0%
(0)
0%
(0)
11%
(1)
J
Josh S (Freeport, Maine, United States)
The replacement I needed

My previous o ring failed and I needed this for my water system to continue working, was able to easily install and now back to normal.

M
Mark Sansone (Waltham, Massachusetts, United States)
O Rings

Great fit fast service thank you

C
Christina

Fit great fast delivery.

C
CHARLES SHARPLESS (Charlotte, North Carolina, United States)
Great customer service

I had a few issues with various shipments and the gentleman that helped me was outstanding. Polite, responsive and sent out what was needed. Really good experience!

L
Larry (Monett, Missouri, United States)

Great

M
Michele Rossi (Cranston, Rhode Island, United States)

very helpful thank you

T
Tim Upton (Oklahoma City, Oklahoma, United States)
Filter o rings

To expensive should come with filters

B
Brian Dudevoir (Alfred, Maine, United States)
Negative

Not good put old ones back in

D
Does this replace the big blue 4.5” x 20” filter from 6 years ago that had 2 black o-rings (Waldport, Oregon, United States)
Wrong O Ring

Totally wrong on ring sent. I will be calling soon to reorder…..