Unalloyed wire electrode for GMA (MIG/MAG) welding of general structural steels, pipes, and cast steels using CO? or mixed shielding gases, depending on the thickness of the base metal. Commonly used in steel construction, machinery, tank, and boiler production. Preheating may be required depending on the plate thickness and carbon equivalent of the base metal. A thin and homogeneous copper coating increases electrical conductivity and protects the wire from rusting.