<h2>3-Pack Black NBR O-Rings – Oil-Resistant Nitrile Rubber Sealing Gaskets</h2> <p>Keep your machinery, plumbing, and hydraulic systems leak-free with these heavy-duty <strong>Nitrile Butadiene Rubber (NBR) O-Rings</strong>. Each pack includes <strong>3 pieces</strong> of precision-formed ring gaskets with a cross-section diameter of <strong>CS 3.5mm</strong> and outer diameter options ranging from <strong>OD 105mm to OD 200mm</strong>. Engineered to deliver reliable sealing performance in demanding industrial and commercial environments, these standard O-rings are a trusted go-to for mechanics, plumbers, and engineers alike.</p> <p>Made in Mainland China.</p> <h3>Why Choose These NBR O-Rings?</h3> <ul> <li> <strong>Superior Oil Resistance:</strong> NBR nitrile rubber compound provides excellent resistance to oils, fuels, greases, and hydraulic fluids — ideal for high-demand sealing applications.</li> <li> <strong>Wide Size Range:</strong> Available in outer diameters from 105mm up to 200mm with a consistent 3.5mm cross-section, covering a broad range of fittings and ports.</li> <li> <strong>Standard Ring Gasket Shape:</strong> Meets standard O-ring dimensional specifications for easy drop-in replacement in existing machinery, valves, and plumbing connections.</li> <li> <strong>Durable Rubber Construction:</strong> Black nitrile rubber resists compression set and maintains its seal over repeated cycles and temperature variations.</li> <li> <strong>Versatile Application:</strong> Suitable for machinery, hydraulic systems, plumbing, pneumatic equipment, automotive, and general industrial use.</li> <li> <strong>Value Pack:</strong> Each order includes 3 O-rings, giving you spares on hand whenever maintenance or replacement is needed.</li> </ul> <h3>Product Specifications</h3> <table style="border-collapse: collapse; width: 100%;"> <tr style="background-color: #f2f2f2;"> <th style="border: 1px solid #ddd; padding: 8px; text-align: left;">Specification</th> <th style="border: 1px solid #ddd; padding: 8px; text-align: left;">Details</th> </tr> <tr> <td style="border: 1px solid #ddd; padding: 8px;">Quantity</td> <td style="border: 1px solid #ddd; padding: 8px;">3 Pieces per Pack</td> </tr> <tr style="background-color: #f2f2f2;"> <td style="border: 1px solid #ddd; padding: 8px;">Material</td> <td style="border: 1px solid #ddd; padding: 8px;">NBR Nitrile Butadiene Rubber</td> </tr> <tr> <td style="border: 1px solid #ddd; padding: 8px;">Color</td> <td style="border: 1px solid #ddd; padding: 8px;">Black</td> </tr> <tr style="background-color: #f2f2f2;"> <td style="border: 1px solid #ddd; padding: 8px;">Cross-Section Diameter (CS)</td> <td style="border: 1px solid #ddd; padding: 8px;">3.5mm</td> </tr> <tr> <td style="border: 1px solid #ddd; padding: 8px;">Outer Diameter (OD)</td> <td style="border: 1px solid #ddd; padding: 8px;">105mm – 200mm (multiple sizes available)</td> </tr> <tr style="background-color: #f2f2f2;"> <td style="border: 1px solid #ddd; padding: 8px;">Shape</td> <td style="border: 1px solid #ddd; padding: 8px;">Ring Gasket</td> </tr> <tr> <td style="border: 1px solid #ddd; padding: 8px;">Standard</td> <td style="border: 1px solid #ddd; padding: 8px;">Standard</td> </tr> <tr style="background-color: #f2f2f2;"> <td style="border: 1px solid #ddd; padding: 8px;">Brand</td> <td style="border: 1px solid #ddd; padding: 8px;">Ouling</td> </tr> <tr> <td style="border: 1px solid #ddd; padding: 8px;">Country of Origin</td> <td style="border: 1px solid #ddd; padding: 8px;">Made in Mainland China</td> </tr> </table> <h3>Applications</h3> <ul> <li>Hydraulic and pneumatic cylinder sealing</li> <li>Industrial machinery and equipment maintenance</li> <li>Plumbing pipe joints and valve connections</li> <li>Automotive oil and fuel system sealing</li> <li>General mechanical gasket replacement</li