MIG (metal inert gas) guns hold consumable electrode wire and connect to a MIG welder to deliver current to the wire and create an arc between the wire and a metal workpiece. The heat from the arc melts and fuses the workpiece material and the wire material to create a weld. MIG guns let the welding operator control the position of the wire during welding tasks. Guns that are used in gas-shielded MIG welding tasks also supply shielding gas to keep contaminants out of the weld pool. General purpose MIG guns are cooled by ambient air and shielding gas during welding tasks, so they do not require an external radiator cooling system and hoses. Push-pull guns have fewer wire-feeding issues than other styles of MIG guns when used with aluminum wire and other soft wires. Spool guns feed electrode wire from a spool mounted on the guns, which helps prevent wire-feeding issues when used with aluminum wire.