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421 Buna-N O-Ring, 70A Durometer, Round, Black, 4' ID, 4-1/2' OD, 1/4' Width (Pack of 5)

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$10.49

$ 4 .99 $4.99

In Stock

About this item

  • Made of Buna-nitrile (also called Buna-N) for use with a variety of fluids and hydrocarbons
  • Can be used across a wide temperature range from -30 degrees F (-34 degrees C) to 250 degrees F (121 degrees C)
  • Round in cross-section to provide a seal between cylindrical overlapping surfaces
  • Durometer (hardness) of 70A for resistance to penetration
  • Meets standards defined by Aerospace Standard AS568A



From the manufacturer

About Us

Sterling Seal and Supply has served the industrial community for over 50 years.

  • Dedicated to Your Success- Built on guiding principles of innovation, leadership, and creating value for customers, we are highly skilled distribution service experts who specialize in providing standard and customized sealing solutions.
  • Our Commitment- Customer success is matched only by our knowledge and experience in developing sealing solutions for a wide range of static and dynamic industrial applications. We offer one of the world’s most extensive and readily available line of shaft seals, O-rings, fluid power seals, HVAC furnace filters, gaskets, Teflon Round Rod, and much more.

Product Line-Up

We serve a wide variety of commercial customers in the Automotive, Chemical, Food & Beverage, Healthcare, and Petroleum industries. Our products meet some of the most stringent standards and are utilized within the government sector around the globe, operating in Space, Land, Sea, and Air.


Emmett T.
Reviewed in the United States on February 27, 2025
Works great
Daisy
Reviewed in the United States on August 31, 2024
Great
Pat S.
Reviewed in Canada on August 7, 2023
good
Customer
Reviewed in Canada on August 20, 2023
Needed rubber seals from an out of business hand pump sprayer I gotThese rings fit perfect
designmore2
Reviewed in the United States on December 23, 2023
The best quality and the best price
D.G.T
Reviewed in Canada on February 11, 2022
Thanks
richard calzini
Reviewed in the United States on October 6, 2022
good o-ring
LARRY
Reviewed in the United States on March 7, 2021
Fit purfect
j-p vaillancourt
Reviewed in Canada on July 31, 2020
what i was looking for
Maureen Nolan
Reviewed in the United States on December 6, 2020
This item fit the project I was working on.
Jack Manifold
Reviewed in Canada on October 7, 2020
used in copper sulfate solution as a ring to seal product
Gene S. Young
Reviewed in the United States on September 15, 2017
Works well
Emmett Brown
Reviewed in the United States on January 27, 2017
Did the job.