Alloy: ASTM B370 | Material: Copper | Shape: Sheet/Plate | Thickness: 0.032 Inch | 21 Gauge | Item Width: 12 Inches | Item Length: 48 Inches Copper Sheet ASTM B370, also known as roofing copper, provides high ductility, durability, and corrosion resistance. B370 is 99% pure copper, and is often referred to by different numbers by different manufacturers as part of branding, but dont let that confuse you. B370 will naturally patina with age. It is used for roofing, interior decoration, and jewelry. Copper is a reddish metal with a face-centered cubic crystalline structure. It reflects red and orange light and absorbs other frequencies in the visible spectrum, due to its band structure, so it has a nice reddish color. It is malleable, ductile, and an extremely good conductor of both heat and electricity. Roofing Architectural Copper This product weighs 5.94 pounds and meets the following specs: ASTM-B370