For builders on a budget, the mild steel flanges are precision cut to insure perfect fitment and are available in 1-3/4" and 1-7/8" port diameters. Made from high grade, mild steel, they are easier to weld than stainless and offer great sealing due to thick warp resistance flanges. These mild steel flanges are sold in pairs and include gaskets and high quality stainless steel header bolts.