Sierra 18-2717 Exhaust Manifold GasketSierra replacement exhaust manifold gasket for Mercury Marine engines and Mercury Race Outboards. Sierra's aftermarket engine parts are manufactured to meet or exceed OEM specifications. For Mercury 12-25 hp 2 cyl.; Interchangeable with:Mercury Marine 27-41475-8; 27-892158; 27-414756; 27-414755; 27-414753; 27-414752; 27-414751; 27-41475; 27-92331; 27-414754; 27-414757;