The Kulsprutepistol m/45 (Kpist m/45), also known as the Carl Gustaf M/45 and the Swedish K SMG, is a 9×19mm Swedish submachine gun (SMG) designed by Gunnar Johnsson, adopted in 1945 (hence the m/45 designation), and manufactured at the Carl Gustafs Stads Gevärsfaktori in Eskilstuna, Sweden. The m/45 was the standard submachine gun of the Swedish Army from 1945 to 1965. It was gradually replaced in Swedish service by updated Ak 4 battle rifles and Ak 5 assault rifles. The last official user of the m/45, the Swedish Home Guard (Hemvärnet), retired it from service in 2007.
The m/45 SMG was developed in 1944–45, with a design borrowing from and also improving on many design elements of earlier submachine guns. The sheet metal stamping techniques used in making the German MP 40, the British Sten, and the Soviet PPSh-41 and PPS-43 were studied in detail. Two designs were tested in 1944, one from Carl Gustafs Stads Gevärsfaktori and one from Husqvarna Vapenfabriks and the prototype from Carl Gustafs Stads Gevärsfaktori was chosen for further development. The first production version was adopted in 1945 as the Kpist m/45. The Danish Hovea M/49 SMG, although similar in appearance, is not a version derived from the m/45. The Hovea was a development of the failed test contender (fm44) from Husqvarna.