Mark-Flugmotoren was a branch of the "Stahlwerk Mark" firm that manufactured aircraft. In 1923 they decided to produce their own engines under the Mark-Flugmotoren name.

-These engines were designed by Professor Dr. Ing. H. Baer. For this reason these engines are sometimes referred to as Mark-Baer.

-We know of three radial engines.

-The St.M. 3, a 3-cylinder radial engine giving 35/39 CV.

"3-cylinder engine"

-The St.M. 5, A radial engine with 5 cylinders that gave 55/63 CV.

"5-Cylinder engine"

-The St.M. 9, A 9 cylinder radial engine giving 110/120 CV.