This set uses mild steel, smooth flowing, CNC mandrel bent tubes, that are hand-welded to ensure each pair is identical to the next. Hedman's unique, gasketless ball and socket collector design allows your Small Block Chevy exhaust system to bolt up, even if it is not perfectly aligned with the header collectors.
Bought these headers for a 1966 c 10 pickup. They fit great. When purchasing these headers they did not show up as fitting a 1966 c 10. But after measuring a 1970 c 10 pickup which the headers show up as fitting we took a chance and they do fit our 1966 c 10 pickup.