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    13 Products
    About O-Rings
    industrial info icon

    Find the right size, compare compatible materials, and choose the best cross section shape for your O-ring.

    Oil-Resistant Buna-N O-Rings

    Made of Buna-N, these O-rings resist grease, hydraulic oil, and motor oil—plus mild chemicals and water. However, Buna-N is not for use with brake fluid. These O-rings are commonly used to create multidirectional seals between two parts in power transmission assemblies, hydraulic cylinders, and pneumatic cylinders. They resist compression and tearing to keep their shape over time. All have shelf life, a cure date, and a traceable lot number printed on the package.
    Inch
    Image of Product. Front orientation. O-Rings. Oil-Resistant Buna-N O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Oil-Resistant Buna-N O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-30 to 212Black509452K205000000000000000
     

    Square-Profile Oil-Resistant Buna-N O-Rings

    With flat edges on all four sides, these O-rings make contact with a larger surface area than round-profile O-rings. The increased contact creates a better seal in static applications, such as hose, pipe, and faucet connections. However, these O-rings aren’t as good of a choice in dynamic applications, where the flat edges cause higher friction that leads to increased wear. Made from Buna-N, they resist tearing and stand up to hydraulic and motor oils.
    Inch
    Image of Product. Front orientation. O-Rings. Square-Profile Oil-Resistant Buna-N O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Square-Profile Oil-Resistant Buna-N O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.203" Wide)
    310
    		1/27/80.475"0.881"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-30 to 212Black254061T4110000000000
     

    High-Temperature Soft Silicone O-Rings

    Easier to compress than standard silicone O-rings, these O-rings create a better seal in enclosures, reservoirs, and other low-pressure equipment. They can withstand temperatures up to 400° F. All have shelf life, a cure date, and a traceable lot number printed on the bag.
    Inch
    Image of Product. Front orientation. O-Rings. High-Temperature Soft Silicone O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. High-Temperature Soft Silicone O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 50A (Soft)ASTM D2000, SAE AS568-85 to 400Red51173N5280000000000
     

    Oil-Resistant Hard Buna-N O-Rings

    Harder than standard Buna-N O-rings, these 90A durometer O-rings are more durable and wear resistant. They resist petroleum and grease, so they’re often used in hydraulic and pneumatic systems. All have shelf life, cure date, and a traceable lot number printed on the bag.
    Inch
    Image of Product. Front orientation. O-Rings. Oil-Resistant Hard Buna-N O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Oil-Resistant Hard Buna-N O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.210" Wide)
    310
    		1/27/80.475"0.895"Durometer 90A (Hard)ASTM D2000, SAE AS568, SAE J200-30 to 250Black505308T3410000000000
     

    Chemical-Resistant Viton® Fluoroelastomer O-Rings

    Made of Viton® fluoroelastomer, these O-rings combine the oil resistance of Buna-N with the heat tolerance of silicone. They also resist a variety of chemicals, including benzene, butyl alcohol, and ethylene glycol. They’re often used to seal hydraulic systems and equipment in crude oil refineries. All have shelf life, a cure date, and a traceable lot number printed on the bag.
    Inch
    Image of Product. Front orientation. O-Rings. Chemical-Resistant Viton® Fluoroelastomer O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Chemical-Resistant Viton® Fluoroelastomer O-Rings.
    Brown—Brown O-rings help you tell Viton® fluoroelastomer apart from other materials.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Choose a
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 75A (Medium)ASTM D2000, SAE AS568, SAE J2000 to 400Black, Brown109464K427000000000000000
     

    High-Temperature Parker S1138 Silicone O-Rings

    Image of Product. Bottom orientation. O-Rings. High-Temperature Parker S1138 Silicone O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. High-Temperature Parker S1138 Silicone O-Rings.
    Use these O-rings in temperatures up to 400° F. Made of Parker S1138 silicone, they’re pure enough for food or pharmaceutical applications—they’re USP VI certified. These O-rings are also FDA compliant for direct contact with food. All come with a cure date and a traceable lot number printed on the bag.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Food Industry Std.
    USP
    Class
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200FDA Compliant 21 CFR 177.2600
    		VI-60 to 400Red259396K281000000000000000000
     

    Water- and Steam-Resistant Parker E0603 EPDM O-Rings

    Image of Product. Front orientation. O-Rings. Water- and Steam-Resistant Parker E0603 EPDM O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Water- and Steam-Resistant Parker E0603 EPDM O-Rings.
    Trusted for their quality and consistency, these E0603 EPDM O-rings resist water, steam, and glycol-based fluids, including brake fluid. They’re often used to seal plumbing and refrigeration systems, since they won’t swell or break down in moist environments. All have a cure date and traceable lot number printed on the bag.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-70 to 250Black759557K286000000000000000000
     

    Oil-Resistant Mil. Spec. Buna-N O-Rings

    Image of Product. Front orientation. O-Rings. Oil-Resistant Mil. Spec. Buna-N O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Oil-Resistant Mil. Spec. Buna-N O-Rings.
    Choose these O-rings for their adherence to strict military standards for material and construction. Made of Buna-N, they stand up to a variety of oils and fuels as well as ammonia, ethylene glycol, and isopropyl alcohol. They’re also resilient and tear resistant. These O-rings are made in the U.S.
    MIL-I-45208—O-rings that meet MIL-I-45208 have undergone rigorous inspection for quality control.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Mil. Spec.
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 65A (Medium)ASTM D2000, SAE AS568, SAE AS3578, SAE J200MIL-I-45208-20 to 250Black255018T333000000000000
     

    Water- and Weather-Resistant Neoprene O-Rings

    Image of Product. Front orientation. O-Rings. Water- and Weather-Resistant Neoprene O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Water- and Weather-Resistant Neoprene O-Rings.
    Resistant to changing weather—from rainwater to sunlight—these neoprene O-rings are good for outdoor use. They’re often used in equipment exposed to the elements, including maritime systems, electrical enclosures, and HVAC units. Compared to EPDM O-rings, these neoprene O-rings have better resistance to oil and chemicals. However, they operate within a narrower temperature range. All have shelf life, cure date, and a traceable lot number printed on the bag.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.210" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-40 to 225Black7594115K31000000000000
     

    Oil- and Abrasion-Resistant Polyurethane O-Rings

    Image of Product. Front orientation. O-Rings. Oil- and Abrasion-Resistant Polyurethane O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Oil- and Abrasion-Resistant Polyurethane O-Rings.
    More abrasion resistant than Buna-N O-rings, these polyurethane O-rings resist mineral oil, motor oil, and ethylene glycol. They have a round profile and are suitable for a wide range of static and dynamic sealing applications. All are sized to the SAE standard AS568.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-40 to 200Black19558K1640000000000
     

    High-Temperature Silicone O-Rings

    Made of silicone, these O-rings can withstand temperatures up to 400° F or higher. They're FDA compliant for direct contact with food, so they're often used on hot food lines. They're also used to seal HVAC systems. All come with a cure date and a traceable lot number printed on the bag.
    Inch
    Image of Product. Bottom orientation. O-Rings. High-Temperature Silicone O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. High-Temperature Silicone O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Food Industry Std.
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200FDA Compliant 21 CFR 177.2600
    		-65 to 400Red259186N329000000000000000
     

    Water- and Steam-Resistant EPDM O-Rings

    Made of EPDM, these O-rings have excellent resistance to water, steam, and glycol-based fluids, including brake fluid. They’re often used to seal plumbing and refrigeration systems, since they won’t swell or break down in moist environments. All have shelf life, a cure date, and a traceable lot number printed on the bag.
    Inch
    Image of Product. Front orientation. O-Rings. Water- and Steam-Resistant EPDM O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Water- and Steam-Resistant EPDM O-Rings.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 70A (Medium)ASTM D2000, SAE AS568, SAE J200-65 to 300Black758785N2120000000000000000
     

    Ultra-Chemical-Resistant FFKM 4079 O-Rings

    Image of Product. Bottom orientation. O-Rings. Ultra-Chemical-Resistant FFKM 4079 O-Rings.
    Image of Attribute. Front orientation. CrossSection view. Contains Annotated. O-Rings. Ultra-Chemical-Resistant FFKM 4079 O-Rings.
    Get the same chemical and heat resistance as Kalrez 4079 without the brand name. Even at 600° F, these FFKM O-rings resist a wide range of chemicals, including acetone, methyl ethyl ketone (MEK), potassium hydroxide, and most acids. All have a cure date and a traceable lot number printed on the bag.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Fractional
    Pkg.
    Dash
    No.
    ID
    OD
    ID
    OD
    Hardness
    Specs. Met
    Temp. Range,
    ° F
    Color
    Pkg.
    Qty.
    1-9
    10-Up
    3/16 Fractional Width (0.21" Wide)
    310
    		1/27/80.475"0.895"Durometer 75A (Medium)ASTM D2000, SAE AS568, SAE J20015 to 600Black18666N2910000000000000
     
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