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Fifty black Buna-N O-rings 38 mm inside diameter 2.5 mm cross section

Zoro Select

Zoro Select O-Ring 38 mm x 2.5 mm Buna-N Black PK50

SKU CH-YXB2-34X6M

Pack of 50 black Buna-N O-rings with 38 mm inside diameter and 2.5 mm cross-section, rated to 70A durometer and -40 to 250 °F

  • Metric 38 mm ID for standard groove fit
  • Buna-N 70A durometer resists oil and fuel
  • 40 °F to 250 °F range handles extreme temps
  • Black colour allows quick visual inspection
  • Pack of 50 supplies multiple repair jobs

O-Ring 38 mm Buna-N Pack of 50

This pack supplies fifty black Buna-N O-rings with a 38 mm inside diameter and 2.5 mm cross-section. They are made to metric dimensions and carry a 70A durometer rating for medium-hard sealing performance. The material withstands temperatures from -40 to 250 degrees Fahrenheit. These rings are metal detectable but not X-ray detectable.

Seals for Metric Hydraulic and Pneumatic Fittings

Maintenance teams and engineers who need metric Buna-N seals in this exact size will find the pack convenient. Buyers requiring FDA-compliant material or X-ray detectable rings for food or pharmaceutical lines cannot use this product. Anyone needing imperial dimensions or a different durometer should look elsewhere.

Critical Spec 38 mm ID 2.5 mm CS Buna-N 70A

The single specification that decides fit is the 38 mm nominal inside diameter combined with the 2.5 mm cross-section and 70A Buna-N hardness. Verify these three values against your groove design before ordering. The 43 mm outside diameter follows from these figures.

Highlights

  • Metric 38 mm ID for standard groove fit
  • Buna-N 70A durometer resists oil and fuel
  • 40 °F to 250 °F range handles extreme temps
  • Black colour allows quick visual inspection
  • Pack of 50 supplies multiple repair jobs

Specifications

BrandZORO SELECT

Questions about this item

How can I confirm the 38 mm inside diameter and 2.5 mm cross-section are correct after installation?

Measure the installed ring with a calibrated gauge; the actual inside diameter should read 38 mm and the actual width 2.5 mm, matching the supplied dimensions.

What comes in the package and what additional items are needed for a typical seal?

The pack contains 50 black Buna-N O-rings sized 38 mm ID by 2.5 mm CS; compatible lubricant or installation tools are not included and must be sourced separately.

Which durometer and temperature rating should I select for a medium-hard seal operating up to 250 °F?

Choose the 70A durometer version listed; it is rated for a continuous range of -40 °F to 250 °F and suits medium-hard sealing requirements.

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