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M4x37 Buna-N O-Ring, 70A Durometer, Round, Black, 37 mm ID, 45 mm OD, 4 mm Width (Pack of 25)

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$12.99

$ 6 .99 $6.99

In Stock

1.:32 Millimeters


2.:32 Millimeters


3.Number of Items:10


About this item

  • Made of Buna-nitrile 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


This O-ring is made of Buna-nitrile (also called Buna-N), round in cross-section, has a durometer of 70A, and is designed for use in a wide variety of sealing applications.

Buna-nitrile can have high tensile strength, resistance to abrasion, tear, and compression set resistance. It is acceptable for temperature applications between -30 degrees F (-34 degrees C) to 250 degrees F (121 degrees C). It is compatible for use with petroleum, HFA, HFB, and HFC fluids, vegetable oil, alcohol, acids, and aliphatic hydrocarbons. Buna-nitrile is vulnerable to acetone, ethers, esters, ozone, sunlight, and weathering, and should therefore not be used in ozone-generating electric motors, welding equipment, or in applications with exposure to UV light.

This O-ring has a shore durometer of 70A. Shore durometer is the hardness of a material, and its resistance to permanent indentation. A higher durometer value indicates greater resistance to indentation on a scale of 0 to 100, with 100 indicating no indentation.

O-rings commonly provide a pressure and fluid seal between cylindrically shaped, overlapping mating surfaces and are commonly seen in engines, faucets, flanges, valves and cylinders of various sorts. They are circular in shape, with a round cross section and a hole in the center, similar to a doughnut. O-rings are available in a number of sizes, and can be ordered based on required nominal inside diameter (ID), outer diameter (OD), and cross-sectional (CS) diameter.


SilverHawk
Reviewed in the United States on August 22, 2020
I purchased these because the bobbin winder on an old 1910 Singer 66 sewing machine would not fit what everyone advertised. Those are 5/8, but the bobbin friction wheel is 3/4". I went with a 30mm outside diameter and an inside diameter of 22mm, and they fit well. It's the only "replacement" friction wheel I could find, and it works.
Tim
Reviewed in Canada on April 30, 2019
Used this for a MF135 hydraulic quadrant arm, and it fit well. Seems to be good quality.
Sparky Steve
Reviewed in Canada on August 7, 2018
These work well if you need a lot of stretch. They don't hold up to UV.
Maria Dunki
Reviewed in Canada on July 30, 2018
as described
daigoji
Reviewed in the United States on July 29, 2018
There's really nothing wrong with them, ordered to replace some that were torn in my water cooled PC, but turned out to be the wrong size. I'll find some use for them eventually. (EKWB HDC 16mm OD fittings use M1.5x16 if anyone else is looking for the right size)
Jaswant Singh
Reviewed in Canada on February 24, 2018
Good quality 0-rings
Alvin Zhao
Reviewed in Canada on January 22, 2018
good product
dt
Reviewed in the United States on May 7, 2017
I needed a rubber washer to fix between a metal washer and the glass light fixture. The center of the washer needed to be 3/8". After searching in the washers, I came across these o-rings. They worked great and made better than the rubber washers..
ToolmanJohn
Reviewed in the United States on February 4, 2017
Bummer that I had to buy a 50 piece bag of these for replacing only one O-Ring. I had a small amount of oil weeping from my motorcycle starter, so I measured the old one and found these available online. The OE version costs almost half, but you only get one. I get 50 here, and I can give away a bunch of them to other guys who have the same motorcycle as me (Yamaha TW200). Put a little grease or oil on the new one before installing, seals up tight. cheap cheap cheap easy fix.
Legal Eagle
Reviewed in the United States on February 17, 2015
RELOADERS REJOICE! Are your Hornady Lock N' Load bushings allowing the dies to pop out of your press from time to time? Is it especially problematic for your powder measure? These O-Rings are the answer. Sure Hornady will send you a metal shim that supposedly corrects the "slippage" problem, but these work so much better and actually fixes the problem cheaply once and for all. They are slightly thicker than the standard Hornady O-Ring that come on the bushings and assure a tight fit with no movement. These are the rings Hornady should have used in the first place. And at this price for 100 O-Rings and two day shipping with Amazon Prime... how can you go wrong? Life is too short for "good enough" or "workarounds" Just buy them... you will not regret it.
Bibliophile
Reviewed in the United States on November 29, 2015
This is the perfect size o-ring for converting a preppy fountain pen from a cartridge to being an ink dropper pen where the barrel of the pen can be completely filled with ink. It is actually a slightly better fit for the Preppy fountain pen than the 010 Buna-N O-Ring, 70A Durometer, Black, 1/4" ID, 3/8" OD, 1/16" Width o-rings although both will work. Add a small dab of silicone grease to the threads and the converted pen will not leak ink at all. Very effective and inexpensive.
RedDevilMutt
Reviewed in the United States on May 19, 2013
I was very pleased to find this product at a decent price and quick delivery. I needed to replace O-rings on a specialty product and feared it was going to be long and expensive process to find the right ones. This purchase turned out to be easy and inexpensive!
MiloshMobile
Reviewed in the United States on December 12, 2013
Plain and simple these little guys worked. I used 8 of them to replace old flat ones from the carb on my motorcycle. The OEM o-rings are 3-4x as expensive and are the same thing. I would buy them again in a heartbeat, though I doubt I'll need to as i now have an extra 92 of them.