110 Copper Foil, Material Copper, Material Grade 110, Mechanical Finish Mill, Overall Width 4 in, Roll Length 50 ft, Length Tolerance +/-0.1 in, Temper O, Tensile Strength 26,000 psi, Maximum Temperature 572 Degrees F, Thickness 0.021 in, Thickness Tolerance 0.0021 in, Standards ASTM B11, ASTM B152, ASTM B370, Fabrication Cold Worked, Heat Treatable Yes, Heat Treatment Annealed, Yield Strength 8,000 psi, Shape Foil, Application Electrical, Length Type Roll, Minimum Temperature 68 Degrees F This copper foil will form a corrosion-resistant green patina over time. It features a plain finish and soft temper, and is commonly used in heat exchangers, fin stock, metal stampings, transformers, printed circuit boards, arts, crafts and construction.