Exhaust manifold leaks in your L5P GM Duramax are not fun. Ensure a leak free seal when installing new or reinstalling your factory exhaust manifolds with these High Performance Exhaust Manifold Gaskets from PPE. This three piece kit features multi-layered 301 stainless steel, PPE Manifold Gaskets are designed to fit both PPE High-Flow Exhaust Manifolds and GM OEM manifolds.