ISO 3601 A0085 Buna-N Nitrile (70A) Metric O-Ring, 70A Durometer, 8.5mm ID x 1.8mm CS (0.335" x 0.071", 12.1mm OD) - Precision-Molded Replacement Sealing Ring for Pumps, Valves & Fittings

Chasing a leak or a slow drip and need the exact metric o-ring size to seal it for good? A worn or wrong-size o-ring lets fluid weep past the joint, drops pressure, and can damage the equipment around it.

This Beaver Island Parts Company replacement o-ring is a single ISO 3601 A0085 o-ring, a standard metric sealing size measuring 8.5mm inside diameter by 1.8mm cross-section (0.335" ID x 0.071" CS, 12.1mm outer diameter), molded in 70A Buna-N Nitrile rubber.

Full Compatibility: ISO 3601 A0085 is an international-standard o-ring size used across pumps, valves, filters, fittings and machinery worldwide. If your application calls for a 8.5mm x 1.8mm o-ring, this is the size.
Installation Note: Clean the groove, inspect the sealing surface, seat the new o-ring without twisting it, and lubricate before assembly.
Pro Tip: Apply Aqua Flex lubricant before installation to ease seating and extend seal life.

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