ER4043 is a 5% Silicon aluminum filler metal that is one of the most widely used aluminum welding alloys for fabrication and general repair in the aluminum welding industry. The smooth running ER4043 is often preferred because of its flowing characteristics and its reduced crack sensitivity over other aluminum welding wires. ER4043 is available in spools and cut lengths for both MIG and TIG welding and is recommended for base metals 3003, 3004,5052, 6061, 6063 and casting alloys 43, 355, 356 and 214. ER4043 has a melting range of 1065-1170 Fand a density of .097 lbs/ci. Its post anodizing color is gray.