Doug's Headers Full Length Headers 2-1/8" Primary 3.500" Diameter Collector Steel - Ceramic H753C3957 4-13/32 in Long

4-13/32 in Long

73-88 Chevelle

7/16-20 in Male Thread

1981-1982 Cadillac Eldorado

Doug's Headers Full Length Headers 2-1/8" Primary 3.500" Diameter Collector Steel - Ceramic H753C3957 4-13/32 in LongProduct Description: Headers Full Length 2. 125 in Primary 3. 5 in Collector Steel Ceramic Big Block Chevy GM F Body 1967 69 X Body 1968 74 Pair Dougs Headers, the most respected name in the header industry since the 60s, began in 1958 as a small muffler shop in East Los Angeles, California. Every Dougs header comes with all the necessary mounting hardware, collector reducers or connector pipes, premium gaskets and detailed installation instruction