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OR-100 Tier1 Lubricated O-Ring

Price $4.99 List Price Price $9.99 Save 50%
Availability: In Stock
Fits into 10 and 20 inch Big Blue water filtration system housings
  • Ships fast!
  • Provides a tight seal in your system, reducing risk of leaks
  • Replace with every two filter changes for best results
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For use in Big Blue whole house water filtration system housings, the OR-100 Tier1 lubricated O-ring helps ensure a tight seal between your system's housing sump and cap, preventing risk of leakage. For best results, use silicone lubricant when installing this part and replace every two filter changes. Stock up on the O-rings your Big Blue housing needs by adding the OR-100 from Tier1 to your cart today. Place your order by 4pm CST for same day shipping.

Experience the Tier1 Difference

Tier1 manufactures high-quality filtration and household products. We take creating and maintaining a healthy home seriously. Products must undergo rigorous testing and meet demanding quality expectations in order to earn the Tier1 badge. Every purchase is backed by the Tier1® Guarantee:

  • Guaranteed Fit
  • Guaranteed Quality
  • Guaranteed Price
Package Qty1
Used In BrandsPentek, Tier1
Manufacturer's IdOR-100
Actual Size (in)5 1/2 inches (inside diameter) x 5 3/4 inches (outside diameter) x 3/16 inches (width)
Actual Size (cm)13.97 x 14.605 x 0.47625
Warranty GuaranteeUnconditional Product Guarantee for Life of the Product

Reduced Contaminants

The TIER1-OR-100 is comparable with the following part numbers


The TIER1-OR-100 fits the following model numbers



  1. The OR-100 o-ring is perfectly doubled up in the package so the o-ring looks too small for your housing at first glance
  2. Once you take it out of the package, you will see the OR-100 o-ring is the correct size for the Big Blue housings