Portable recorder developed for professional broadcast use. The first model was made of wood. Its spring-powered transport system (controlled by a governor and wound by a crank in front) eliminated the risk of a dead battery during recording and enabled a smaller, lighter unit. Radio programs that interviewed ordinary people on the street using the M Type enjoyed a surge in popularity. After the recorder appeared in the satirical comic strip "Densuke," about just such a young reporter, the unit came to be nicknamed the "Densuke."