Metric Buna O-Rings

OneMonroe’s Metric Buna O-Rings are engineered to provide reliable sealing performance across a variety of industrial and commercial applications. Made from high-quality Buna-N (Nitrile) rubber, these O-rings are known for their excellent resistance to oils, fuels, and other petroleum-based products, making them ideal for use in environments where durable, leak-proof seals are essential. Buna-N’s resilient properties allow it to maintain its integrity even in challenging temperatures, ranging from -40°F to 250°F, ensuring these O-rings can withstand both low and high-stress conditions with ease. With a broad range of metric sizes available, OneMonroe ensures you’ll find the right fit for your exact specifications.

Our Metric Buna O-Rings are crafted to offer outstanding resistance to abrasion and tearing, providing long-lasting performance in rigorous applications. This makes them well-suited for automotive, aerospace, marine, and hydraulic systems, as well as in general maintenance and repair settings. The unique chemical composition of Buna-N allows these O-rings to endure pressure and friction over extended periods without compromising their sealing capabilities, making them a reliable choice for static and dynamic sealing tasks. Each O-ring is manufactured to precise industry standards, ensuring a dependable fit and function in every installation.

With OneMonroe, you’re getting more than just a product; you’re receiving a commitment to quality and expertise. Our team is dedicated to supporting your projects with high-quality metric Buna O-Rings that meet both industry standards and specific customer requirements. We provide technical support to help you select the best O-ring for your application, offering detailed product specifications and guidance. Trust OneMonroe to deliver durable, efficient, and cost-effective sealing solutions tailored to meet the demands of your unique projects.

For more information, please see: Comparison Properties Chart, PTFE Encapsulated O-rings, Material Shelf Life, and O-ring Groove Design Chart.

Item #	IntegrationID	Type	Material	Cross Reference	Cross Section Width	Durometer	Inside Diameter	Product Guides
328 X 4 B-90	N/A 121924	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 328.00 mm	N/A Seal Guides
329 X 4 B-70	N/A 121925	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 329.00 mm	N/A Seal Guides
329 X 4 B-90	N/A 121926	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 329.00 mm	N/A Seal Guides
330x4.00B70	N/A 121927	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 330.00 mm	N/A Seal Guides
330 X 4 B-90	N/A 121928	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 330.00 mm	N/A Seal Guides
331 X 4 B-70	N/A 121929	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 331.00 mm	N/A Seal Guides
331 X 4 B-90	N/A 121930	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 331.00 mm	N/A Seal Guides
332x4.00B70	N/A 121931	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 332.00 mm	N/A Seal Guides
332 X 4 B-90	N/A 121932	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 332.00 mm	N/A Seal Guides
333 X 4 B-70	N/A 121933	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 333.00 mm	N/A Seal Guides
333 X 4 B-90	N/A 121934	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 333.00 mm	N/A Seal Guides
334 X 4 B-70	N/A 121935	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 334.00 mm	N/A Seal Guides
334 X 4 B-90	N/A 121936	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 334.00 mm	N/A Seal Guides
335x4.00B70	N/A 121937	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 335.00 mm	N/A Seal Guides
335 X 4 B-90	N/A 121938	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 335.00 mm	N/A Seal Guides
336 X 4 B-70	N/A 121939	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 336.00 mm	N/A Seal Guides
336 X 4 B-90	N/A 121940	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 336.00 mm	N/A Seal Guides
337 X 4 B-70	N/A 121941	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 337.00 mm	N/A Seal Guides
337 X 4 B-90	N/A 121942	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 337.00 mm	N/A Seal Guides
338 X 4 B-70	N/A 121943	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 338.00 mm	N/A Seal Guides
338 X 4 B-90	N/A 121944	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 338.00 mm	N/A Seal Guides
339 X 4 B-70	N/A 121945	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 339.00 mm	N/A Seal Guides
339 X 4 B-90	N/A 121946	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 339.00 mm	N/A Seal Guides
340x4.00B70	N/A 121947	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 340.00 mm	N/A Seal Guides
340 X 4 B-90	N/A 121948	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 340.00 mm	N/A Seal Guides

N/A
121924

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 328.00 mm

N/A Seal Guides

329 X 4 B-70

N/A
121925

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 329.00 mm

N/A Seal Guides

329 X 4 B-90

N/A
121926

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 329.00 mm

N/A Seal Guides

330x4.00B70

N/A
121927

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 330.00 mm

N/A Seal Guides

330 X 4 B-90

N/A
121928

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 330.00 mm

N/A Seal Guides

331 X 4 B-70

N/A
121929

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 331.00 mm

N/A Seal Guides

331 X 4 B-90

N/A
121930

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 331.00 mm

N/A Seal Guides

332x4.00B70

N/A
121931

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 332.00 mm

N/A Seal Guides

332 X 4 B-90

N/A
121932

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 332.00 mm

N/A Seal Guides

333 X 4 B-70

N/A
121933

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 333.00 mm

N/A Seal Guides

333 X 4 B-90

N/A
121934

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 333.00 mm

N/A Seal Guides

334 X 4 B-70

N/A
121935

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 334.00 mm

N/A Seal Guides

334 X 4 B-90

N/A
121936

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 334.00 mm

N/A Seal Guides

335x4.00B70

N/A
121937

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 335.00 mm

N/A Seal Guides

335 X 4 B-90

N/A
121938

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 335.00 mm

N/A Seal Guides

336 X 4 B-70

N/A
121939

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 336.00 mm

N/A Seal Guides

336 X 4 B-90

N/A
121940

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 336.00 mm

N/A Seal Guides

337 X 4 B-70

N/A
121941

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 337.00 mm

N/A Seal Guides

337 X 4 B-90

N/A
121942

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 337.00 mm

N/A Seal Guides

338 X 4 B-70

N/A
121943

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 338.00 mm

N/A Seal Guides

338 X 4 B-90

N/A
121944

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 338.00 mm

N/A Seal Guides

339 X 4 B-70

N/A
121945

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 339.00 mm

N/A Seal Guides

339 X 4 B-90

N/A
121946

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 339.00 mm

N/A Seal Guides

340x4.00B70

N/A
121947

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 340.00 mm

N/A Seal Guides

340 X 4 B-90

N/A
121948

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 340.00 mm

N/A Seal Guides