9 gauge HRPO (Hot Rolled Pickled and Oiled) steel typically has a thickness of about 0.148 inches (3.76 mm). Its mechanical properties include a yield strength of around 30,000 to 40,000 psi and a tensile strength of approximately 50,000 to 70,000 psi, depending on the specific alloy and processing. The steel exhibits good ductility and formability, making it suitable for various applications, including automotive and structural components. Additionally, the pickling process enhances corrosion resistance by removing scale and impurities from the surface.