The FMK-3 is a selective fire, blowback operated submachine gun of Argentine origin and was designed by Fabricaciones Militares in 1974. It is chambered in 9 mm, with a rate of fire of 650 rounds per minute. 20, 32, and 40 round magazines are available for the FMK-3. 30,000 were produced for the Argentine military by 1991. Rarely, some variants are found with fixed stocks. The FMK-3 is also produced for the civilian market, as a semi-automatic-only version, named the FMK-5.