These Hooker BlackHeart Long Tube Headers are for 1967-1969 Camaro/Firebird (also known as Gen 1 F-body) with Big block Chevrolet engines. Constructed from 2 inch lightweight 18 gauge, mandrel bent, 304 SS. They feature 3 inch, long-transition collectors and merge spears for maximum flow. Plus a 3/8 inch thick flange for strength and a superior seal. All this and still work with the stock transmission cross-member and manual transmission Z-bar linkage. These are designed to work with BlackHeart part #BH13192 which is our 3" header-back exhaust system.