The Edelbrock Manifold Gasket is designed to match with Performer Series manifolds and heads. It features an embossed silicone bead surrounding the ports for a clean positive seal. This gasket also features Micropore MP-2N ultra-modern environmentally safe gasket material, and they provide excellent sealing on rough, irregular flange surfaces. It is impervious to most chemicals, including gasoline, alcohol, coolant and oils. This gasket provides optimum sealing in intermittent operating temperatures up to 400 degrees Fahrenheit.