Sur La Table Platinum Professional Quarter Sheet Pan 21045QS, 9" x 13" Developed in Pittsburgh, PA, by USA Pan, our commercial-quality pan meets the highest standards for performance and durability Thick aluminized steel offers superior heat transfer, as well as corrosion and rust resistance The thickness is based on years of performance data to deliver perfectly even heat distribution and a lifetime of use Steel wire is added to pan rim for extra strength and resistance to warping The unique fluted design with corrugated construction maximizes strength and impact resistance, and resists warping and denting