proflow header extractor flanges, for chevrolet gm ls, steel, 3/8 in. thick, 1.90 in. diameter bore, each

Proflow offers a variety of header flange sizes and shapes to mate your heads and headers. These 3/8 thick flanges are precision-cut to meet your ports, reduce warping, and prevent leaks. Proflow header flanges keep your tubes in place without the big price tag.