Shop by Brand Mercury OutboardGasket/Gasket Kit Back Power Head Gasket Set 27-803663A99/803663A99 Viewer:306 OEM No.: 27-803663A99/803663A99 For MERCURY outboard 9.9, 15, 18 HP You May Also Be Interested In Gasket 27-8537024/853702 4 Gasket 27-8129395/812939 5 Spark Plug 9701-1-1015/BR7HS-10 Guide, Exhaust 6B4-41137-00-5B