304 / 304L / 304H SS Pipe Tube is the most common stainless steel. The steel contains both chromium (between 18–20%) and nickel (between 8–10.5%)metals as the main non-iron constituents. It is an austenitic stainless steel. It is less electrically and thermally conductive than carbon steel and is essentially non-magnetic. It has a higher corrosion resistance than regular steel and is widely used because of the ease in which it is formed into various shapes.