Shop by Brand Mercury OutboardGasket/Gasket Kit Back Power Head Gasket Set 27-803663A99/803663A99 Viewer:303 OEM No.: 27-803663A99/803663A99 For MERCURY outboard 9.9, 15, 18 HP You May Also Be Interested In Gasket 27-853987/853987 Power Head Gasket Set 27-42364A92/42364A92 Piston Ring 6E5-11610-20 0.50 Float 13250-98110-000