Header Dies are metal tools that are used for punching or fastening tube holes in bolt-on type headers. These are manufactured or made by a lot of engineering, design and tooling shops around the world. The headers is clamped and indexed across the header die fastening the tube holes all along. The row of punches can be fit into place by using a set of back-up bars. These are also used in disengaging each of these rows of punches. It also has an adjustable clamp bar that can be positioned in and out of the tube hole pattern on the header.