NGK (3626) B9HS-10 Standard Spark Plug, Pack of 1 You can depend on NGK for quality and reliability Constructed from durable material.Corrugated ribs prevent flash over Insulators constructed from 99 percent pure alumina silicate Solid core offers superior heat dissipation and conductivity This is a non-auto plug.It is for Mercury Outboard Marine engines. It is compatible only for mercury model no 7.5 & 95, Year 1985-1979