The Mitsubishi Kasei was a two-row, 14-cylinder air-cooled radial engine built by Mitsubishi Heavy Industries and used in a variety of World War II Japanese aircraft, such as Mitsubishi J2M and Mitsubishi G4M. The Mitsubishi model designation for this engine was A10 while it was an experimental project, in service it was known as the MK4, and known as the Ha101 & Ha111 by the Army and Kasei by the Navy. Wikipedia