Very Rare 1967-69 Chevrolet Big Block Factory High Performance Oval port heads #3919840 and original valve covers with correct oil drip rails. The 840 heads were used from May 1967 through May 1969. These particular heads show a casting date code of C 12 9 (March 12, 1969). These heads would be correct for 1969 Passenger 427/425hp, Chevelle and Camaro 396/375hp & 427/425hp, Corvette 427/435hp, and Chevy II 396/375hp. Excellent original condition on matching pair. Used on Corvette, Chevelle and Camaro. Let me know if you need more pictures. Bring your best offer! 312-656-0700