The Suomi KP/-31 (Finnish: Suomi-konepistooli m/31 or "Finland-machine-pistol mod. 1931") is a Finnish submachine gun that was mainly used during World War II. It is a descendant of the M-22 prototype and the KP/-26 production model, which was revealed to the public in 1925. It entered service in Finland in 1931, and remained in use until the 1980s.
