ER4043&nbsp;- MIG Aluminum Welding Wire - 1 Lb x 0.030" (4 SPOOLS) ER4043, commonly referred to as AlSi5", has a 5% silicon and is the oldest and one of the most widely used aluminum welding wires for general purpose applications Less sensitive to weld cracking than other aluminum alloys and the 5% silicon content lowers the melting point, increases fluidity of the weld puddle and leaves a bright shiny weld deposit. ER4043 is commonly used for welding grades 6061, 6063, 5052, 3004, 3003 and cast alloys 356.0, 357.0, 413.0, and 443.0 to name just a few Melting range is 1065 F 1170 F, density is 0.097 lbs/in3 and post anodizing color is gray 1 Lb of wire per Spool - Available diameters: 0.030", 0.035" and 0.045" - Available Spool Quantities 1, 2 and 4-Pack. Select your choice from the menu.