Dr. Kroeber und Sohn GmbH of Treuenbrietsen developed a two-stroke engine of its Kroeber brand.

-It had two horizontally-opposed cylinders, with single ignition and gave 18 CV at 2,700 rpm.

-It was manufactured between 1936 and 1939. It was the M4 model.

-The full name of the company is Kroeber and Köller GmbH.

-That is, the engine that is presented in the Köller chapter belongs to the same company, being a name of two partners. (Kroeber und Sohn GmbH).

-In Köller an M-3 is shown. Now we present an M-4 as it is exhibited in the Munich Museum.

“Kroeber-Koller M-4”

“Another view of an M-4”

From Appendix 12: Two-cylinder boxer engine, installed.

“Installation on a light aircraft”