Also known as Boss O-rings, these Viton® fluoroelastomer O-rings are made for tube fittings with a straight-thread connection. With a 90A durometer, they’re harder and more durable than standard Viton® fluoroelastomer O-rings. Use them to seal high-pressure parts, such as fuel injectors and heavy duty hydraulic cylinders. They resist a wide range of chemicals, including benzene, butyl alcohol, and ethylene glycol. To install, place them behind the threads on a male fitting. As you tighten against a female fitting, the O-ring compresses to form a tight seal. All have shelf life, a cure date, and a traceable lot number printed on the bag.

Also known as Boss O-rings, these O-rings are made for tube fittings with a straight-thread connection. Made of Viton® fluoroelastomer, they resist a variety of chemicals, including benzene, butyl alcohol, and ethylene glycol. They combine the oil resistance of Buna-N with the heat tolerance of silicone, so they’re often used to seal hydraulic systems or machines that process crude oil. To install, place them behind the threads on a male fitting. As you tighten against a female fitting, the O-ring compresses to form a tight seal. All have shelf life, a cure date, and a traceable lot number printed on the bag.

Also known as boss O-rings, these O-rings are sized to fit straight-thread fittings to prevent leaks. They were first designed for biomedical use, are made of FDA-listed materials, and are USP VI certified. Their high purity makes them a common choice for food and pharmaceutical applications. Made of silicone, they resist heat up to 400° F for use in high-temperature lines. All have a cure date and a traceable lot number printed on the bag. These O-rings are not cleaned and bagged.

Softer than standard silicone O-rings, these O-rings form a better seal in enclosures, reservoirs, and other low-pressure equipment. They withstand temperatures up to 400° F or higher. Also known as Boss O-rings, they’re made for tube fittings with a straight-thread connection. They resist water, oil, and alcohol, so they’re often used to seal food processing equipment. They’re also FDA compliant for direct contact with food. To install, fit them behind the threads on a male fitting. As you tighten against a female fitting, the O-ring compresses to form a tight seal. All have a cure date and a traceable lot number printed on the bag.

Also known as Boss O-rings, these O-rings are made for tube fittings with a straight-thread connection. They’re fluorosilicone, which stays flexible in temperatures as low as -65° F, so they form better seals than Viton® fluoroelastomer O-rings in cold environments. These O-rings withstand ethanol and ethylene glycol. They also meet MIL-R-25988 standards for quality and performance. To install, place them behind the threads on a male fitting. As you tighten against a female fitting, the O-ring compresses to form a tight seal. Shelf life, a cure date, and a traceable lot number are printed on the bag.

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.

Keep a range of sizes on hand so that you always have the O-ring you need. Also known as boss O-rings, the O-rings in these assortments are sized to fit straight threaded fittings to prevent leaks. With a 90A durometer hardness, they're more wear resistant than standard Buna-N O-rings. They withstand motor oil, hydraulic fluid, and mild chemicals, so they're often installed in hydraulic and pneumatic systems.

The same chemical and heat resistance as Kalrez 4079 without the brand name. These FFKM O-rings resist a wide range of chemicals, including acetone, methyl ethyl ketone (MEK), potassium hydroxide, and most acids—even at scorching temperatures of 600° F. Also known as boss O-rings, they’re sized to fit straight-thread fittings to prevent leaks. Use them to seal fittings in high-temperature chemical lines. All have cure date and a traceable lot number printed on the bag.

Also known as Boss O-rings, these O-rings are used in tube fittings with a straight-thread connection. Made of PTFE, they withstand extreme temperatures and harsh chemicals such as fluorinated solvents, ethanol, and acetone. They’re also rigid, which makes them more difficult to install than flexible O-rings. These O-rings are FDA compliant for direct contact with food. You’ll find them in pump shafts, mixing tanks, and other equipment that processes chemicals or pharmaceuticals. Install them behind the threads on a male fitting. As you tighten against a female fitting, the O-ring compresses to form a tight seal. All have a cure date and a traceable lot number on the bag.

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.

Also known as boss O-rings, these neoprene O-rings seal straight-thread fittings in valve housings, outdoor enclosures, and saltwater applications. They resist water, UV rays, and mild chemicals, making them good for use both indoors and outdoors. Compared to EPDM O-rings, these neoprene O-rings have better resistance to oil and chemicals. All have shelf life, cure date, and a traceable lot number printed on the bag.

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.