Shop by Brand Mercury OutboardGasket/Gasket Kit Back Power Head Gasket Set 27-803663A99/803663A99 Viewer:294 OEM No.: 27-803663A99/803663A99 For MERCURY outboard 9.9, 15, 18 HP You May Also Be Interested In Gasket 27-43007-5/43007 5 Gasket Kit, Powerhead 27-43779A87 Pin, Cross 17-30632/30632 Sleeve 354580/0354580