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Sierra 18-7121 Marine O-Ring for OMC, Mercury & Mercruiser Sterndrive - 3.100" I.D. x 0.135" Width

Manufacturer

Picture for manufacturer Sierra

Part Number

18-7121
13 reviews
Sale Price

$8.67

In Stock (6)

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Usually delivered within 2 days

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Product Details

The Sierra 18-7121 is a precision-fit marine O-ring designed for use with OMC, Mercury, and Mercruiser outboard and sterndrive applications. Measuring 3.100" inner diameter x 0.135" width, this O-ring provides a reliable seal in demanding marine environments where water intrusion and pressure resistance are critical.

Key Features:

  • Precision dimensions: 3.100" I.D. x 0.135" width
  • Designed for OMC, Mercury, and Mercruiser sterndrive and outboard applications
  • Meets or exceeds original equipment specifications
  • One O-ring included per package

Cross-Reference / Supersedes:

  • OMC Stern Drive: 308621
  • Mercury Marine: 25-35029
  • Mercruiser Stern Drive: 25-35029, 27-882613, 802231
  • Mallory: 9-76651
  • GLM: 82350

Sierra International is a leading manufacturer of marine aftermarket parts, with each component engineered to meet or exceed the performance of the OEM part it replaces. The 18-7121 O-ring is an ideal direct replacement for a worn or damaged seal in compatible sterndrive and outboard systems.

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