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Gaskets for 37° Flared Tube Fittings
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Prevent leaks from temperature fluctuations and vibration that can loosen 37° flared tube fittings. In general, you should match your gasket material to your fitting material. But, if you have a brass fitting, you can use a copper gasket.
Gaskets without a coating are best for fittings that are exposed to harsh chemicals, such as antifreeze, which can dissolve the threadlocker coating.
Threadlocker-coated gaskets offer a more secure hold than uncoated gaskets, so they’re best for areas with high vibration.
For technical drawings and 3-D models, click on a part number.
Thread | Temperature, °F | ||||||||
---|---|---|---|---|---|---|---|---|---|
For Tube OD | Dash Size | Size | Type | Thickness | Maximum Pressure, psi | Min. | Max. | Each | |
304 Stainless Steel | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | Not Rated | 2500° | 00000000 | 00000 |
Threadlocker-Coated 304 Stainless Steel—Orange | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | -40° | 300° | 00000000 | 0000 |
316 Stainless Steel | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | Not Rated | 2500° | 00000000 | 0000 |
Threadlocker-Coated 316 Stainless Steel—Black | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | -40° | 1200° | 00000000 | 0000 |
Threadlocker-Coated 316 Stainless Steel—Green | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | -40° | 300° | 00000000 | 0000 |
Aluminum | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 3,000 | Not Rated | 1200° | 00000000 | 0000 |
Copper | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | -420° | 800° | 00000000 | 0000 |
Threadlocker-Coated Copper—Purple | |||||||||
1/4" | 04 | 7/16"-20 | UN/UNF (JIC) | 0.183" | 20,000 | -40° | 300° | 00000000 | 0000 |
Gaskets for 45° Flared Tube Fittings
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Stop leaks from variations in temperature and vibration that can loosen 45° flared tube fittings. Made of copper, these gaskets are for use with brass fittings.
Gaskets without a coating are best for fittings that are exposed to harsh chemicals, such as antifreeze, which can dissolve the threadlocker coating.
Threadlocker-coated gaskets offer a more secure hold than uncoated gaskets, so they’re best for areas with high vibration.
For technical drawings and 3-D models, click on a part number.
Oil-Resistant Hard Buna-N O-Rings for Tube
Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these are for use in tube fittings with a straight-thread connection. They're made of hard Buna-N, which is resilient and offers excellent resistance to wear, grease, petroleum fluids, and motor oil. These O-rings have a round profile and are suitable for a wide range of static and dynamic sealing applications. They're sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 90A (Hard) | ASTM D2000, SAE AS568, SAE J200 | -10° to 210° | Black | 100 | 00000000 | 00000 |
Oil- and Abrasion-Resistant Polyurethane O-Rings
for Tube Fittings with Straight-Thread Connection
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Commonly called Boss O-rings, these polyurethane O-rings are for use in tube fittings with a straight-thread connection. They resist mineral oil, motor oil, and ethylene glycol. All have a round profile and are suitable for a wide range of static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 70A (Medium) | ASTM D2000, SAE AS568, SAE J200 | -40° to 200° | Black | 1 | 00000000 | 00000 |
Ultra-Chemical-Resistant Rigid PTFE O-Rings
for Tube Fittings with Straight-Thread Connection
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These temperature- and chemical-resistant O-rings prevent leaks in tube fittings that have a straight-thread connection, also known as O-ring boss fittings. Because they’re PTFE, these O-rings are slippery, won’t tear, and resist harsh chemicals such as acetone, fluorinated solvents, methanol, and boric acid. They’re also made of FDA-listed materials, so they’re safe to use in food production lines. However, they’re rigid, which makes them more difficult to install than flexible O-rings. They come in standard dash number sizes according to SAE AS568A.
For technical drawings and 3-D models, click on a part number.
Fractional | Actual | |||||||||||||
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Dash Number | For Tube OD | Wd. | ID | OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 5/64 | 23/64 | 1/2 | 0.072" | 0.351" | 0.495" | Durometer 55D (Hard) | FDA Compliant 21 CFR 177.1550, SAE AS568 | -300° to 500° | White | 25 | 0000000 | 00000 |
Ultra-Chemical-Resistant Kalrez 4079 O-Rings
for Tube Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these Kalrez 4079 O-rings are for use in tube fittings with a straight-thread connection. They’re inherently softer and more compressible than PTFE O-rings with comparable chemical resistance. Use them with acetone, methyl ethyl ketone (MEK), potassium hydroxide, and most acids. All have a round profile and are suitable for a wide range of static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Each | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 75A (Medium) | ASTM D2000, SAE AS568, SAE J200 | 30° to 600° | Black | 00000000 | 000000 |
Chemical-Resistant Mil. Spec. Viton® Fluoroelastomer
O-Rings for Tube Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these Viton® fluoroelastomer O-rings are for use in tube fittings with a straight-thread connection. They meet MIL-R-83248. They resist chemicals such as benzene, butyl alcohol, and ethylene glycol. All have a round profile and are suitable for a wide range of static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 75A (Medium) | ASTM D2000, MIL-R-83248, SAE AS568, SAE J200 | 0° to 400° | Black | 100 | 00000000 | 000000 |
Chemical-Resistant Low-Temperature Fluorosilicone
O-Rings for Tube Fittings with Straight-Thread Connection
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Flexible even at temperatures as low as -75° F, these fluorosilicone O-rings will keep your fittings free from leaks. They’re often used on fuel and coolant hose because fluorosilicone resists many chemicals, including ethanol and ethylene glycol. Also known as Boss O-rings, these O-rings work with tube fittings with a straight-thread connection, such as BSPP, UN/UNF, and most metric fittings.
These O-rings meet MIL and ASTM standards for the chemical and physical properties of fluorosilicone. They also meet SAE AS568A for standard O-ring sizing.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 70A (Medium) | ASTM D2000, MIL-R-25988, SAE AS568 | -75° to 390° | Blue | 10 | 0000000 | 000000 |
Chemical-Resistant Hard Viton® Fluoroelastomer O-Rings
for Tube Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these hard Viton® fluoroelastomer O-rings are for use in tube fittings with a straight-thread connection. They resist a wide range of chemicals, including benzene, butyl alcohol, and ethylene glycol. All have a round profile and are suitable for both static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 90A (Hard) | ASTM D2000, SAE AS568, SAE J200 | 0° to 400° | Black | 25 | 00000000 | 00000 |
High-Temperature Soft Silicone O-Rings
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Able to withstand temperatures up to 400° F, these silicone O-rings are softer than standard silicone O-rings for a better seal in low-pressure applications. 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.
For technical drawings and 3-D models, click on a part number.
Fractional | Actual | |||||||||||
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Dash Number | For Tube OD | ID | OD | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
Wd.: 5/64 Fractional (0.072" Actual) | ||||||||||||
904 | 1/4" | 23/64 | 1/2 | 0.351" | 0.495" | Durometer 50A (Soft) | ASTM D2000, SAE AS568 | -85° to 400° | Red | 10 | 00000000 | 00000 |
Water- and Steam-Resistant EPDM O-Rings for
Tube Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these EPDM O-rings are for use in tube fittings with a straight-thread connection. They resist water, steam, ethanol, and ethylene glycol. All have a round profile and are suitable for a wide range of static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Specifications Met | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 70A (Medium) | ASTM D2000, SAE AS568, SAE J200 | -70° to 250° | Black | 90 | 00000000 | 000000 |
Water-Resistant Neoprene O-Rings for Tube
Fittings with Straight-Thread Connection
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Also known as Boss O-rings, these neoprene O-rings are for use in tube fittings with a straight-thread connection. They resist water, ammonia, ethylene glycol, and isopropyl alcohol. All have a round profile and are suitable for a wide range of static and dynamic sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 70A (Medium) | -10° to 170° | Black | 90 | 000000000 | 000000 |
High-Temperature High-Purity Silicone O-Rings
for Tube Fittings with Straight-Thread Connection
![](/prerenderstable/mvPRE/contents/gfx/imagecache/110/1108t118c1-1633114395-p9@halfx_637686931997426567.png?ver=imagenotfound)
Also known as Boss O-rings, these silicone O-rings are for use in tube fittings with a straight-thread connection. They withstand temperatures up to 400° F and bounce back after compression. All have a round profile and are suitable for a wide range of sealing applications. These O-rings are sized to the SAE standard AS568.
For technical drawings and 3-D models, click on a part number.
Dash Number | For Tube OD | Wd. | ID | OD | Hardness | Temperature Range, °F | Color | Pkg. Qty. | Pkg. | |
904 | 1/4" | 0.072" | 0.351" | 0.495" | Durometer 70A (Medium) | -60° to 400° | Red | 50 | 00000000 | 00000 |