Nitrile Rubber Washers

Shop nitrile rubber washers in every OD, ID and thickness we stock. Nitrile is outstanding oil, fuel and grease resistance — making it the go-to choice for automotive, hydraulic systems, fuel lines and industrial machinery. Rated for −40°F to 257°F. Fast shipping and bulk pricing on every order.

Not sure if Nitrile is right for your job? Read our Nitrile material guide for a full compound comparison, or compare all 7 washer materials side by side. New to washer sizing? See how to measure OD, ID & thickness, then shop the full catalog.

Popular Nitrile uses: automotive and HVAC.

Nitrile (Buna-N) washer properties

The oil-service standard

Nitrile washers (also called Buna-N) are the default seal wherever petroleum is present: crankcase drain plugs, hydraulic fittings, compressors, gearboxes, fuel filters, grease-lubricated machinery and automotive hardware generally. Nitrile keeps its flexibility to −40°F — colder than Viton tolerates — at a fraction of Viton's price. Where nitrile taps out: modern ethanol-blended fuels, aggressive chemicals, sustained heat past 257°F, and anything in direct sunlight. The full head-to-head is in Buna vs Viton; for outdoor water service switch to EPDM.

Bulk nitrile washers

Every size here carries automatic volume pricing, and shops running nitrile washers by the box can quote larger and mixed-size runs through the bulk & wholesale program.

Nitrile washer FAQ

Is nitrile the same as Buna-N?

Yes — nitrile, Buna-N and NBR all name the same acrylonitrile-butadiene rubber.

Are nitrile washers fuel resistant?

Good with straight gasoline and diesel; ethanol blends (E15/E85) swell nitrile over time — spec Viton for modern fuel systems.

Can I use nitrile washers outside?

Not in sunlight — UV and ozone crack nitrile within seasons. Outdoors, use EPDM or neoprene unless oil forces Viton.

Nitrile vs neoprene washers?

Nitrile for real oil/fuel duty; neoprene for balanced weather-plus-incidental-oil service. If it drips petroleum, it's nitrile's job.