1920—1932: From Versuchsbau Hellmuth Hirth to Elektronmetall G.m.b.H., Stuttgart-Cannstatt (EC )

1920Hermann Mahle joins Versuchsbau Hellmuth Hirth
1921First series production of light-alloy pistons in Europe
1922Ernst Mahle joins the company
1924Company renamed Elektronmetall G.m.b.H., Stuttgart-Cannstatt (EC )
New lightweight pistons for motorsport activities
1926Hermann Mahle appointed Commercial Director
1927Ernst Mahle appointed Technical Director
1929Series production of air, oil, and fuel filters
1930First cylinder liners made of nitrided steel
1931Ring carrier piston registered for patent