The Type 99 Mark 1 machine gun and Type 99 Mark 2 machine gun were Japanese versions of the Oerlikon FF and Oerlikon FFL autocannons respectively. They were adopted by the Imperial Japanese Navy (IJN) in 1939 and served as their standard aircraft autocannon during World War II.

The Nakajima J1N1 Gekkō is a twin-engine aircraft used by the Imperial Japanese Navy during World War II. A prototype first flew in May 1941. The first full production variant of the Gekkō, the J1N1-C was a reconnaissance aircraft, although many of these underwent field modification into night fighters; in addition, a night fighter variant, the J1N1-S was later put into production. Towards the end of the war, J1N1 pilots also undertook kamikaze anti-shipping missions. The Gekkō was given the Allied reporting name "Irving".