Diebel-Cox Manufacturing Company was established in 1901 in Philadelphia, Pennsylvania. The company was founded by William Diebel, who designed a light runabout vehicle powered by a 7-horsepower, 2-cylinder air-cooled engine. This innovative cooling system featured rings with radiating arms that were shrunk onto the cylinder casting, which was a distinctive characteristic of the vehicle.

The runabout was priced at $650, which was considered reasonable for the time. However, despite its unique design and competitive pricing, Diebel-Cox Manufacturing Company did not survive beyond the year of its introduction, marking a brief existence in the early automotive industry.