I decided to fit manifolds to my Dodge Van and bought a special cheap manifold. After replacing a double gasket, sealant and even the manifolds I couldn't fix a few small leaks. Then I came across these seals in the forum of the site. After a simple install, the leaks I struggled with for months are gone! I will never use any other gaskets than these on my manifolds! As others have said, be careful not to bend when installing as they are brittle and will delaminate.