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Black Buna-N O-ring 74 mm inside diameter 3 mm cross section pack of 25

Zoro Select

Zoro Select O-Ring 74 mm ID 3 mm Buna-N Black PK25

SKU CH-7PMM-4YMT1

Pack of 25 black Buna-N O-rings with 74 mm inside diameter and 3 mm cross-section for sealing applications

  • Metal-detectable Buna-N seals for contamination-sensitive lines
  • 74 mm ID and 3 mm cross-section fit standard metric glands
  • 70A durometer resists extrusion up to 250 °F
  • Pack of 25 reduces re-order frequency
  • Operates down to -40 °F for cold-environment reliability

Product Identity

The Zoro Select O-Ring is a metric Buna-N seal with a 74 mm inside diameter and a 3 mm cross-section. It is supplied in a pack of 25 black rings rated to a 70A durometer hardness. The material operates across a temperature range of -40 to 250 degrees Fahrenheit.

Fit and Limitations

These rings suit maintenance kits and production lines that need a medium-hard, metric Buna-N seal in this exact size. They are not FDA compliant, so they cannot be used in food or pharmaceutical contact applications. Buyers needing X-ray detectable materials or different durometer ratings must source alternative parts.

Sustained Use

The Buna-N compound maintains its sealing properties through repeated thermal cycles within the stated range. The medium-hard durometer resists extrusion and compression set during prolonged static or dynamic service. Performance remains consistent as long as operating temperatures and chemical exposure stay within material limits.

How it compares

Measured against everything we stock in Bearings, Belts & Drive Components, at today’s prices. Recalculated every night.

Price $8.99
Cheaper than about 90% of the 693 comparable items (median $35.99).

Specifications

Product
Brand nameZORO SELECT

Questions about this item

What groove dimensions do I need to seal with the 74 mm inside diameter and 3 mm cross-section?

Machine a groove with a 74 mm inside diameter and 3 mm width so the ring sits flush and compresses evenly.

Will the Buna-N 70A durometer hold up against hydraulic oil in my older press?

Buna-N resists petroleum-based hydraulic fluids, and the 70A hardness handles typical press pressures without extruding.

How can I verify the rings meet the -40 °F to 250 °F range after installation?

Pressurise the system at room temperature, then cycle to the extremes; no leakage or hardening means the material is performing within spec.

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