Mr Gasket Exhaust Header Gasket 4816G; MLS Square Port 1.900 in. 1.850 in. for Chevy 396-454

Multi-Layered Steel (MLS) exhaust and header collector gaskets are designed for extreme cylinder pressures produced by high horsepower-high compression turbo-charged, supercharged, and nitrous oxide engines. Manufactured from three stainless steel layers, resists corrosion, will not burn through or push out and maintains maximum fastener torque retention. Stress formed inner and outer layer embossments act like springs that rebound under exhaust flange clamp load, creating force to seal excessive exhaust pressure produced from cylinder heads. Withstands different combinations of cylinder head (aluminum) and exhaust header or manifold (steel) materials, will not deteriorate from scrubbing action caused by different expansion rates in aluminum and steel.