Vulcanized O-Rings from The O-Ring Store


Example of a 1/2″ cross-section being vulcanized.

A vulcanized O-Ring is an O-Ring made from vulcanized O-Ring cord stock. The vulcanization process creates a strong and durable bond, making it suitable for a variety of applications. Vulcanized O-Rings are a more readily available and cost effective solution to having large custom molded O-Rings made. The O-Ring Store stocks and is tooled to vulcanize many cross-sections in both metric and standard sizes.  Vulcanized O-Rings are available 6 inches (150mm) inside diameter and above from The O-Ring Store.

When to consider a vulcanized O-Ring:

  • When the size you need is unavailable or has a long lead time.
  • When the O-Ring you need is too large to be molded.
  • When factory minimum is too high.
  • Test or prototype quantity on a large size you would like to test before ordering a production quantity.
  • When your cross-section is unavailable in a molded O-Ring.
  • Large diameter O-Rings or large cross-sections O-Rings.

Available Materials for Vulcanized O-Rings:

Link to vulcanized O-Rings: Vulcanized O-Rings

High Temperature O-Ring Applications


Not all high temperature O-Ring applications require the same O-Ring compounds. Some materials react differently to certain types of heat. In this blog we will go over which compounds will perform well in each common high heat environment.

Silicone – Vinyl-meth-silicone VMQ

Silicone is often what most customers assume is the go-to material for a high temperature O-Ring. Silicone is also FDA compliant and non contaminating, so you see if often in applications involving food handling, as well as medical devices. Not recommended for dynamic or abrasive environments, or gasses due to high permeability.

Viton – Fluorocarbon FKM

Often known as Viton,  fluorocarbon O-Ring materials exhibit great high heat resistance to petroleum and fuel products. Because of this, it is the most common O-Ring among the automotive industry. Standard fluorocarbon compounds are not suitable for applications involving super heated water or steam.

EPDM – Ethylene-Propylene

EPDM is the go-to elastomer for hot water and steam applications. It often seen in water processing equipment, industrial steamers, appliances, automotive cooling systems, pressure washers, and marine equipment. EPDM is not suitable for any applications involving petroleum based products.

Fluorosilicone – FVMQ

Fluorosilicone is great for static sealing of fuels up to +392°F. Because of Its great temperature range and fuel resistance it is widely used in aerospace applications. It is also seen in automotive fuel applications for more extreme fuel applications.  It still has the physical properties of silicone, so it is limited to static sealing applications.

Teflon – PTFE

Teflon is a non-elasted thermoplastic with a wide operating temperature range (-100°F to +500°F). It is virtually chemically inert, and has a very low coefficient of friction. Teflon is often seen in chemical processing, or extreme environment applications. Tenfon is a non-elastic material, but The O-Ring Store also stocks Teflon/PTFE encapsulated Viton or Silicone.


Japanese Industrial Standard O-Rings (JIS B 2401)

The Japanese Industrial standard O-Ring sizes (JIS B 2401) are O-Rings that are unique to Japan’s automotive industry. Often listed as metric O-Rings, these sizes are used in specific automotive applications in Japan. The P series is used for dynamic sealing, G series for static or fixed applications, S series for special sizes, and V series for vacuum flange fittings. At The O-Ring Store, our part numbers will be formatted the same as our standard metric O-Rings, but will have the JIS numbers added to the description. The O-Ring Store keeps good stock of the JIS sizes in both Buna-N 70 Durometer and Viton 75 Durometer.

Part Number Format: N1.50X002.5

Material Prefix (N for Buna-N V for Viton) | Cross-Section | Inside Diameter


See also : O-Ring Materials for Automotive Applications

Automotive O-Ring Materials

automotive-applicationsThe automotive industry uses many O-Rings in many different compounds. Getting the right O-Ring size and material will be the difference between a working product or a product that will fail prematurely. Below we will be listing each compound often seen being used for automotive O-Rings and their typical automotive applications, as well as uncommon applications we come across that work excellent for our customers.

Buna-N (-40°F to +250°F)

Buna Nitrile is the most common O-Ring material across all industries. In automotive it is seen a lot where it is in contact with oils below the temperature of 250°F. It is also resistant to automotive antifreeze, straight gasoline (no ethanol or other additives), and transmission fluids.

Limitations for Buna-N in the automotive industry are temperatures over 250°F, ethanol and other fuel additives, and automotive refrigerants for air conditioning. For standard automotive fuels a Viton or Fluorocarbon O-Ring material is the go-to. The compatible material for automotive refrigerants is HNBR (highly saturated nitrile rubber).

Viton/FKM/Fluorocarbon (-15°F to +400°F)

Viton, also known as FKM or Fluorocarbon, is one of the most common O-Ring materials in the automotive industry due to its resistant to most fluids involved in automotive applications. It will be resistant to all automotive oils up to a temperature of 400°F, and most automotive fuels.

Limitations for this material are automotive refrigerants, and fuels with a high ethanol content or other other additives. To see if this material would be compatible with your type of fuels you may check the chemical compatibility guide. If Viton is not compatible with your type of fuel, you may upgrade to either Viton extreme ETP or Fluorosilicone.

HNBR (-40°F to +300°F)

HNBR, or highly saturated nitrile rubber, is a material similar to Buna-N, but it undergoes a process of being dissolved in a solvent, and then introduced to a catalyst  and hydrogen gas to hydrogenate the nitrile. This allows the HNBR compound to be resistant to automotive refrigerants, and type A steering fluid. It also has a slightly higher temperature resistance of 300°F.

EPDM (-65 to +300°F)

EPDM is the only standard compound that is resistant to automotive brake fluids. That makes it a valuable material to the automotive industry, but it is does not work well for much else. EPDM is not recommended for any petroleum based oils or fuels because it will cause significant swelling and consequently fail in your application.

Fluorosilicone (-76° to +392°F)

Fluorosilicone is a material that combines the temperature range  of silicone and the chemical and fuel resistance of a fluorinated rubber. It is most often seen with aviation fuels and racing fuels. We often see this compound headed to very cold places to replace Viton seals along fuel lines that get too cold for Viton seals. Because of it’s excellent low temperature flexibility, it can seal where no material can.

Fluorosilicone, because it does retain physical properties of silicone, is restricted to static applications only.

Viton Extreme ETP (-8 to +482°F)

Viton Extreme ETP is a compound that is overkill in most automotive applications unless you are using fuels with high alcohol content, or specialty treated fuels. It is a good replacement for a dynamic seal you would normally use fluorosilicone in, but needs to be wear resistant. You may look at the chemical compatibility guide to see if this material is right for you.

If you have any additional questions, or would like to get a quote, feel free to contact us!

1005 Warner Ave, Suite A Lewiston ID 83501 | Phone (208) 413-6377 Fax (208) 413-6719


OEM Startup Assistance

Our OEM Startup Assistance Program


We would like to help you get your project or company started, and create a lifelong business relationship with you and your company. Check out how we can help below!


The O-Ring Store will help you find the right O-Rings or seals for your project. We want to make your procurement of our products to be easy!


Your initial order will be credited 50% up to $500.00 to help you save money while you are in your early development stages.


Using our social media pages, website, or blog, we will market our products using your product, company, or crowdfunding campaign to help create a win-win situation for marketing your product and ours.


Lets get Started!

Click here to get the Startup Assistance Application

Phone (208) 413-6377 Email:

How To Order O-Rings Online

How To Order O-Rings Online

We like to make getting O-Rings easy. So in this blog post we will go over the steps to get the right O-Ring on our website

Step 1: The Right Material

There are many places to get the information for choosing your material.

The Chemical Resistance Guide: This is an alphabetical listing of chemicals that you can use check the compatibility of O-Ring materials. It also lists a generic selection guide below the chart on the page for general applications.


Step 2: The Right Size

The O-Ring Size Chart: The O-Ring Size Chart lists all of the AS568 standard O-Rings in their nominal fraction dimensions, their exact dimensions in decimals, and their exact dimensions in millimeters. Once you find the size you need, you can easily navigate to your size in the AS568 O-Ring section. There is also a material selection list with links below the chart.


For metric O-Rings, you will first choose your material, then the cross section, and they will be listed by inside diameters.


Step 3: Checking Out

Once you are have all the O-Rings you need added to your shopping cart, you are ready to check out. Your shopping cart and checkout link will be located at the top right corner of the website. cart

Need Help?:

If you are needing any help at all you can use the live chat/email button that appears at the bottom right of your screen at any time. For any special applications or assistance the contact us page will list emails for the sales team that can help you with any O-Ring or other sealing needs.


Here is a quick video for a visual of how to order O-Rings from our website.

MAX Truck O-Ring kits

MAX Truck O-Ring Assortmentsmax

The MAX Truck O-Ring kit is the kit you need to have on hand if you like having a good supply of O-Rings with the best chance of having the O-Ring size you need. The MAX Truck Kit is the perfect O-Ring kit for service trucks, repair shops, or retail counters. This is a huge assortment with 1,431 pieces covering 81 different sizes of O-Rings.  It is available in Buna-N 70 durometer (90 duro. BOSS and Flange kits), Buna-N 90 Durometer, Viton FKM 75 (90 duro. BOSS and Flange kits), and Viton FKM 90 Durometer. Don’t let your equipment or job be stalled by not having one of these in your inventory!

Click Here to Order Yours!

The MAX Truck O-Ring kit Includes :

  • Box 1 -000 Series 1/16″ CS (sizes and dimensions listed on the AS568 O-Ring Chart) :
  • -006 through -018 25pcs/EA
  • -019 through -022 20pcs/EA
  • -023 through -026 15pcs/EA
  • -028 through -030 15pcs/EA

Box 2 -100 Series 3/32″ CS (sizes and dimensions listed on the AS568 O-Ring Chart) :

  • -109 through -118 25pcs/EA
  • -119 through -120 20pcs/EA
  • -121 through -127 15pcs/EA
  • -128 through -129 10pcs/EA
  • -131 10pcs
  • -133 10pcs
  • -135 5pcs

Box 3 -200 Series 1/8″ CS (sizes and dimensions listed on the AS568 O-Ring Chart) :

  • -210 through 214 20pcs/EA
  • -215 through -222 15pcs/EA
  • -223 through -224 10pcs/EA
  • -226 10pcs
  • -228 10pcs
  • -232 10pcs
  • -236 10pcs

Box4 Boss SAE -900 Series:

  • -903 #3 Fitting 15pcs
  • -904 #4 Fitting 25pcs
  • -906 #6 Fitting 15pcs
  • -907 #7 Fitting 25pcs
  • -908 #8 Fitting 25pcs
  • -910 #10 Fitting 25pcs
  • -912 #12 Fitting 15pcs
  • -916 #16 Fitting 10pcs

Box 5 Flange Seal Kit:

  • Flange Fitting #8 10pcs
  • Flange Fitting #12 10pcs
  • Flange Fitting #16 10pcs
  • Flange Fitting #20 5pcs
  • Flange Fitting #24 5pcs
  • Flange Fitting #32 5pcs

FDA O-Ring Materials


Not only do you need an FDA compliant O-Ring material, but you need an O-Ring material that is going to work in your application. To make this easier, here is the most common of the FDA compliant O-Ring materials and their most common uses in relation to applications needing FDA compliance.

Buna-N FDA O-Rings

Buna-N is the most commonly used O-Ring material and is available in black or white FDA compliant compounds.

  • General purpose applications.
  • Food handling machinery with incidental food contact.
  • Room temperature oils, condiments, liquids, etc.
  • Cold food handling machinery (to -40°F/-40°C).
  • White Buna-N for creams, lotions, etc. needing no black color in mixture.

Temperature range -40°F to 250°F (-40°C to 121°C).

Silicone O-Rings

Silicone is a material that is most often identified as FDA compliant. With its temperature range it can be used when the other materials would not be recommended. It does have poor abrasion, tearing, and cutting resistance, so it is primarily used in static sealing applications. All Silicone comes FDA standard from The O-Ring Store.

  • Good for most FDA applications.
  • High temperature FDA applications not involving water or steam.
  • Static, long term sealing on food handling or medical equipment.
  • High temperature oils, greases, and other liquids besides water.

Temperature range -75°F to 400°F (-60°C to 204°C). (Water up to 250°F)

EPDM O-Rings

EPDM is the best and most popular choice for water and steam applications. It is good for many FDA applications not involving oils. It is also available in a separate compound with FDA and NSF compliance for drinking water. All EPDM comes FDA standard from The O-Ring Store.

  • Equipment producing steam. Example: Steamers, dishwashers.
  • Water filtration.
  • Winery and brewery equipment.

Temperature range -65°F to 300°F (-51°C to 149°C). (400°F/204°C for water or steam)

Viton Brown FDA O-Rings

Viton Brown FDA is not used as much as the other compounds, but is a good high temperature material with good physical properties that is still a FDA compliant material.

  • High temperature applications not involving steam.
  • Mineral Oils, vegetable oils, and greases.
  • Alcohols
  • Propane and natural gas.

Temperature Resistance -20°F to 400°F (-29°C to 204°F)

Teflon Encapsulated O-Rings

Teflon® Encapsulated O-Rings Viton®, Silicone, or EPDM

Encapsulated o-rings are o-rings consisting of a seamless and uniform Teflon® encapsulation which completely encloses a rubber core material. Elastomer/rubber core material are a choice of Silicone, Viton or EPDM. The combination of  these components creates an o-ring that is virtually chemically inert and compression set resistant for use in harsh sealing environments. This combination of chemically resistant polymer jacket over a low-compression set elastomer provides unique properties for a range of demanding applications.

Size not listed, special requirements or large quantities please click this link to Request a Price Quote.

Teflon® Encapsulated O-Rings

Elastomeric, rubber O-Rings are susceptible to high friction and limited resistance to aggressive chemicals and gas permeation. Solid PTFE O-Rings are rigid with no effective memory and high compression set. Teflon® Encapsulated O-Rings combine the resilience and sealing force of an elastomer with the chemical resistance of Teflon®. This is accomplished by the use of an elastomeric core of silicone or Viton® with a relatively thin encapsulation of Teflon® FEP or PFA fluoropolymer. The result is an elastomeric PTFE seal with enhanced sealing capability.

Our Teflon® Encapsulated O-Rings are solvent-resistant and chemically inert (except for attack by alkaline metals, fluorine and some halogenated compounds at high temperatures), yet have an elastomeric memory near that of rubber O-Rings. The more commonly specified FEP encapsulation also has an extremely low coefficient of friction (.1 to .2) and very low permeability to gases, making Teflon® Encapsulated O-Rings virtually a universal seal for use in hostile environments.

Encapsulated Teflon® O-Ring with Viton® or Silicone core general specifications:

Overview: Teflon® Encapsulated O-Rings are o-rings consisting of a seamless and uniform Teflon® encapsulation which completely encloses a rubber core material. Elastomer/rubber core materials are a choice of Silicone, Viton, EPDM. The combination of these components creates an o-ring that is virtually chemically inert and compression set resistant for use in harsh sealing environments.


  • High Chemical Resistance: Chemical attack and swelling are the primary causes of O-Ring failure. ENCAP-O-Seal™ encapsulated o-rings are virtually chemically inert.
  • Outperforms solid PTFE O-Rings: ENCAP-O-Seal™ encapsulated o-rings match the chemical and temperature resistance of solid PTFE O-Rings, ENCAP-O-Seal™ encapsulated o-rings possess properties of elasticity and recovery which are crucial in many sealing applications.
  • Economical: ENCAP-O-Seal™ encapsulated o-rings economically and effectively replace Kalrez and other exotic O-Ring compounds. ENCAP-O-Seal™ encapsulated o-rings will decrease downtime and hence increase profitability wherever corrosive fluids and gases cause premature seal failure.
  • Wide Temperature Range: ENCAP-O-Seal™ encapsulated o-rings withstand breakdown caused by industrial solvents and corrosive materials at elevated temperatures from -60° C/-75° F to +205° C/400° F. (See General Specifications)
  • Non Stick Surface: Provides easy cleanup of viscous materials.
  • Low Coefficient of Friction: .2 on metal. Self-lubricating surface.
  • Sanitary: Eliminates contamination of fluids by elastomers. Sterilizable and autoclavable. FDA compliant, USP Class VI compliant, NSF compliance ~ available for specific applications.
  • Unlimited Sizes: Available in standard and metric sizes from .059″ cross section x ½” I.D. to virtually unlimited larger sizes.
  • Low Compression Set: ENCAP-O-Seal™ encapsulated o-rings consist of either a solid silicone or Viton® core encapsulated in Teflon® FEP/PFA resin (with .010 to .045 wall depending cross section) which meets or exceeds requirements of L-P389A and ASTM-D-2166.

Size Range for Teflon Encapsulated O-Rings*

Standard AS/BS Cross Sections




Smaller Inside diameters are available upon request


  1. Encapsulation material: Teflon® FEP: Tetraflouroethylene-Hexafluoropropylene. Dupont Teflon PFA:   Tetraflouroethylene-Perfluoro (Propyl Vinyl Ether).
  2. Core material: Dow Corning Silicone, DuPont Viton® Type A, Viton® GFS elastomers.
  3. Continuous service temperature:
    1. Teflon FEP Encapsulation with Silicone Core: 400F/204C. to -75F/-60C
    2. Teflon PFA Encapsulation with Silicone Core: 500F/260C to -75F/-60C
    3. Teflon FEP Encapsulation with Viton® Core: 300F/149C to -10F/-23C
    4. Teflon FEP Encapsualtion with HT Viton® Core: 400F/204C to -10F/-23C
    5. Teflon PFA Encapsualtion with HT Viton® Core: 400F/204C to -10F/-23C
  1. Coefficient of friction: .1 to .2 on metal surfaces.
  1. Water absorption: <0.01.
  1. Average total shore A hardness:
    1. 85-90 shore A for solid silicone core.
    2. 90-95 shore A for solid viton core.
    3. 75-80 shore A for hollow silicone core.
  1. FDA Compliance: The clear TEFLON® FEP encapsulation of the ENCAP-O-SEAL o-ring complies with part 177 of Title 21 of the Food and Drug Administration’s regulations for safe use as articles or components of articles for producing, manufacturing, processing, preparing, treating, packing, transporting or holding food in accordance with regulation 177.1550.00

Food Handling | Irrigation | Oil & Gas | Pool & Spa | Semiconductors | Automotive | Aviation
Chemical Processing | Spray Foam | Hydraulic | Pneumatic | Fluid Power | Specialty OEM

We make getting o-rings easy. We have the broadest selection of O-Rings available for the maintenance and repair industry. We offer great pricing for OEM and large national accounts and the specifications needed for military, automotive and aerospace seals.

The O-ring Store, LLC
1005 Warner Ave, Suite A
Lewiston ID 83501
Phone 208-413-6377
Fax 208-413-6719
We make getting o-rings easy!

Broadest selection of O-Rings easily available.

We make getting o-rings easy. We have the broadest selection of O-Rings available for the maintenance and repair industry. We offer great pricing for OEM and large national accounts and the specifications needed for military, automotive and aerospace seals.

Food Handling | Irrigation | Oil & Gas | Pool & Spa
Semiconductors | Automotive | Aviation
Chemical Processing | Spray Foam | Specialty OEM
Hydraulic | Pneumatic | Fluid Power

We have added product and services that have been and will be a great benefit to our customers in 2016. We have the basic compounds, Buna-N, Viton (FKM), Silicone, EPDM, Neoprene, Urethane and Teflon and have done very well supplying our customers with their needs. We have added additional inventory and selections in Viton Extreme, Color-Select O-Rings, Buna-N FDA, Buna-N FDA White, Buna-N Mil-Spec, Fluorosilicone, HNBR Green, Perfluorocarbons (FFKM) – commonly referred to as Kalrez® or Chemraz®, Teflon Coated, Teflon Encapsulated, Viton GFLT,  Viton GLT, Viton Mil-Spec, Viton FDA, as wells as many other special production compounds. With the increased selection and capabilities 2016 is going to be a very exciting year for us, our vendors and most importantly our customers. Please visit our website, or call our Sales Director at 208-413-6377.