The Messerschmitt Bf 110, often known unofficially as the Me 110, is a twin-engine Zerstörer (Destroyer, heavy fighter), fighter-bomber (Jagdbomber or Jabo), and night fighter (Nachtjäger) developed in Nazi Germany in the 1930s and used by the Luftwaffe during World War II. Hermann Göring was a proponent of the Bf 110, believing its heavy armament, speed, and range would make the Bf 110 the Luftwaffe’s premier offensive fighter. Early variants were armed with two MG FF 20 mm cannon, four 7.92 mm (.312 in) MG 17 machine guns, and one 7.92 mm (.312 in) MG 15 machine gun for defence (later variants would replace the MG FFs with MG 151s and the rear gunner station would be armed with the twin-barreled MG 81Z). Development work on an improved type to replace the Bf 110 - the Messerschmitt Me 21