Cometic 1984+ Harley-Davidson Stock Big Twin .010 Copper Base Gasket - 2 Pack

What you get in this package are two Cometic copper base gaskets, specifically sized at .010 inch undersize. These are meant for 1984 and newer Harley-Davidson Big Twin engines.

Copper is a solid material for base gaskets because it can conform well to the mating surfaces, helping to create a strong seal. The .010 undersize means these gaskets are slightly smaller than stock, which is often done during engine rebuilds to achieve a specific compression ratio or to account for machine work on the cylinders or cases. It's important to ensure your engine cases and cylinders have been machined to match this undersize for a proper fit and seal.