Standard rubber seals with excellent fit. However, there is very misleading/confusing misinformation on the shim kit packaging. There is a connection that these gaskets are chemically treated to be self-sealing. I have seen no evidence of this; They are simply molded rubber gaskets packaged with no additional protection other than a cellulose based cardboard box which has no protective film or an additional plastic bag to hold some type of sealing film on the gaskets. I have been using Fel Pro…