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Description
Sierra 18-3921 Mercury Standard Piston Rings
Sierra high-quality engine parts are designed to meet OEM specifications.
- Bore Size: 3.125 / Standard
Interchangeable with:
- GLM
- 14240
- Mallory
- 9-54233
- Mercury Marine
- 39-93481A12
- Wiseco
- 3125KD
California Residents: 
WARNING Cancer and Reproductive Harm - P65Warnings.ca.gov
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