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
228 X 4 B-90	N/A 121724	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 228.00 mm	N/A Seal Guides
229 X 4 B-70	N/A 121725	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 229.00 mm	N/A Seal Guides
229 X 4 B-90	N/A 121726	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 229.00 mm	N/A Seal Guides
230x4.00B70	N/A 121727	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 230.00 mm	N/A Seal Guides
230 X 4 B-90	N/A 121728	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 230.00 mm	N/A Seal Guides
231 X 4 B-70	N/A 121729	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 231.00 mm	N/A Seal Guides
231 X 4 B-90	N/A 121730	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 231.00 mm	N/A Seal Guides
232x4.00B70	N/A 121731	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 232.00 mm	N/A Seal Guides
232 X 4 B-90	N/A 121732	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 232.00 mm	N/A Seal Guides
233 X 4 B-70	N/A 121733	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 233.00 mm	N/A Seal Guides
233 X 4 B-90	N/A 121734	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 233.00 mm	N/A Seal Guides
234 X 4 B-70	N/A 121735	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 234.00 mm	N/A Seal Guides
234 X 4 B-90	N/A 121736	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 234.00 mm	N/A Seal Guides
235x4.00B70	N/A 121737	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 235.00 mm	N/A Seal Guides
235 X 4 B-90	N/A 121738	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 235.00 mm	N/A Seal Guides
236x4.00B70	N/A 121739	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 236.00 mm	N/A Seal Guides
236 X 4 B-90	N/A 121740	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 236.00 mm	N/A Seal Guides
237x4.00B70	N/A 121741	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 237.00 mm	N/A Seal Guides
237 X 4 B-90	N/A 121742	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 237.00 mm	N/A Seal Guides
238x4.00B70	N/A 121743	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 238.00 mm	N/A Seal Guides
238 X 4 B-90	N/A 121744	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 238.00 mm	N/A Seal Guides
239 X 4 B-70	N/A 121745	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 239.00 mm	N/A Seal Guides
239 X 4 B-90	N/A 121746	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 239.00 mm	N/A Seal Guides
240x4.00B70	N/A 121747	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 70	N/A 240.00 mm	N/A Seal Guides
240 X 4 B-90	N/A 121748	N/A Metric Standard O-Ring	N/A Buna	N/A	N/A 4.00 mm	N/A 90	N/A 240.00 mm	N/A Seal Guides

N/A
121724

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 228.00 mm

N/A Seal Guides

229 X 4 B-70

N/A
121725

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 229.00 mm

N/A Seal Guides

229 X 4 B-90

N/A
121726

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 229.00 mm

N/A Seal Guides

230x4.00B70

N/A
121727

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 230.00 mm

N/A Seal Guides

230 X 4 B-90

N/A
121728

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 230.00 mm

N/A Seal Guides

231 X 4 B-70

N/A
121729

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 231.00 mm

N/A Seal Guides

231 X 4 B-90

N/A
121730

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 231.00 mm

N/A Seal Guides

232x4.00B70

N/A
121731

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 232.00 mm

N/A Seal Guides

232 X 4 B-90

N/A
121732

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 232.00 mm

N/A Seal Guides

233 X 4 B-70

N/A
121733

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 233.00 mm

N/A Seal Guides

233 X 4 B-90

N/A
121734

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 233.00 mm

N/A Seal Guides

234 X 4 B-70

N/A
121735

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 234.00 mm

N/A Seal Guides

234 X 4 B-90

N/A
121736

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 234.00 mm

N/A Seal Guides

235x4.00B70

N/A
121737

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 235.00 mm

N/A Seal Guides

235 X 4 B-90

N/A
121738

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 235.00 mm

N/A Seal Guides

236x4.00B70

N/A
121739

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 236.00 mm

N/A Seal Guides

236 X 4 B-90

N/A
121740

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 236.00 mm

N/A Seal Guides

237x4.00B70

N/A
121741

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 237.00 mm

N/A Seal Guides

237 X 4 B-90

N/A
121742

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 237.00 mm

N/A Seal Guides

238x4.00B70

N/A
121743

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 238.00 mm

N/A Seal Guides

238 X 4 B-90

N/A
121744

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 238.00 mm

N/A Seal Guides

239 X 4 B-70

N/A
121745

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 239.00 mm

N/A Seal Guides

239 X 4 B-90

N/A
121746

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 239.00 mm

N/A Seal Guides

240x4.00B70

N/A
121747

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 70

N/A 240.00 mm

N/A Seal Guides

240 X 4 B-90

N/A
121748

N/A Metric Standard O-Ring

N/A Buna

N/A

N/A 4.00 mm

N/A 90

N/A 240.00 mm

N/A Seal Guides