Since the 1950s, A-OX has been one of the largest, most complete distributors of industrial gas and welding supply in the upper Midwest. Today, A-OX Welding Supply comprises 7 locations in South Dakota, North Dakota, and Iowa with a headquarters and central warehouse in Sioux Falls, SD. We have our own fleet of bulk tankers and delivery trucks that service customers across a 5-state region including South Dakota, North Dakota, Minnesota, Iowa, and Nebraska.