A plain gasket which can be fabricated in any required configuration. With adequate bolting, #540 is effective and economical, especially on flanges with concentric serrations. In addition to exceptional mechanical strength, other characteristics of #540 include heat conductivity and excellent resistance to high pressures, high temperatures and chemical attack. If gasket is not finished machined, minimum width should be 50% more than the thickness of the metal. The only limitation on dimensions of the flat metal gasket is the width of metal sheet commercially available.