Big Block Chevy Engine Overhaul Gasket Kit 396 427 454 BBC/260-1009 Replacement for 1965-1975 Chevrolet Bel Air 1975-1978 GMC C25 Pickup 1965-1970 Pontiac Strato-Chief 1968-1974 GMC K35/K3500 Pickup SEALED WELLIt securely seals the gasket set so that oil leaks will be prevented each time it pools lubricant oil as it goes to the cylinder head's drain back opening. Aside from oil, this gasket also helps prevent the entry of other harmful materials to the valve train. HIGHLY DURABLEIt is highly durable and less prone to breakage. to provide exceptional service life and reliability. PROFESSIONAL CUSTOMER SERVICEVincos has the professional production technology.We inspected every product before sending out,to ensure you have the best quality product,and the best value.If you have any problem please feel free to contact us.For more effectively helpness, please let us know your car make model and show the issue by pictures .We would take highly attention of your opinions and demands,to improve our products and service for you.Enjoy your shopping time. WITHSTAND HARSH CONDITIONSAdvanced manufacturing technology ensures durability and optimum operation in higher or lower temperatures. NOTEThe attachment to the gasket set must be just right-not too tight and not too loose. Any of these two conditions can ruin the gasket's efficiency; consequently, the valve cover itself.