This Header is made for big block Chevrolet's in street rods when tight fit and performance are a factor. Virtually eliminates ground clearance problems. Fits most chassis without cross member beneath center of engine block. Constructed of 1-7/8" Primary tubes and a 3" Collector. Fits 396-454 Engines in 1932 - 1950 Cars and some late models. Please specify if you have a Mark5 engine. Includes all hardware necessary for instillation.