ISO 3601 B0258 FKM Fluorocarbon Metric O-Ring, 70A Durometer, 25.8mm ID x 2.65mm CS (1.016" x 0.104", 31.1mm 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 B0258 o-ring, a standard metric sealing size measuring 25.8mm inside diameter by 2.65mm cross-section (1.016" ID x 0.104" CS, 31.1mm outer diameter), molded in 70A Fluorocarbon (FKM) rubber.

Full Compatibility: ISO 3601 B0258 is an international-standard o-ring size used across pumps, valves, filters, fittings and machinery worldwide. If your application calls for a 25.8mm x 2.65mm 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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