The Haenel MK 556 (German: Maschinenkarabiner) is a gas-operated selective-fire 5.56×45mm NATO assault rifle designed by C.G. Haenel in Germany. The MK556 was finalised in September 2020, and it is a fully automatic version of an earlier Haenel design, the CR 223, which was already in limited use by law enforcement agencies since 2017. On 14 September 2020, the Haenel MK 556 was selected by the German Armed Forces (Bundeswehr) as a replacement for the G36, making it the first service rifle used by the Bundeswehr produced by a company other than Heckler & Koch, who had submitted their own designs.