Mercury - Cylinder head stb - 900-8M0217525 Yamaha-F40B-2005 Everything is precision-matched to Mercury’s

Everything is precision-matched to Mercury’s factory tolerances

Choosing an OEM Mercury Marine part isn’t just about matching numbers—it’s about dependable protection backed by engineering that understands real boating conditions

Yes — the rubber and composite materials resist salt

Remove caulking with ease

Acceleration is quick and confident — you will feel the boat rise cleanly and respond without hesitation

Mercury - Cylinder head stb - 900-8M0217525 Yamaha-F40B-2005 Everything is precision-matched to Mercury’sCylinder head stb WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings. ca. gov.