Metric O-Rings | ISO 3601 & JIS Sizes

Metric O-Rings are seals sized in millimeters by inside diameter (ID) and cross-section (CS), used to seal imported machinery, hydraulic fittings, pumps, and valves built to ISO 3601 and JIS specs. If a standard inch (AS568) O-Ring won't seal, you likely need a metric size. We carry them in Buna-N (NBR), Viton (FKM), EPDM, silicone, plus HNBR, FFKM, and PTFE for specialty jobs. Most sizes come in 70 and 75 Shore A durometer, with 90 on request.

Common sizes ship from stock. The rest we make to order or bring in from the factory. Shop by size to match your exact ID x CS in millimeters. Not sure which size or compound you need? Our team can help you match the groove and the fluid, so you order the right part the first time. The O-Ring Store LLC is ISO 9001:2015 certified.