Knee mortar: Japanese Type 89 50 mm light mortar, called "knee mortar" by American troops who thought it looked designed to be fired braced on the knee (which it was not).
K 44: German 128 mm gun
KwK 36: German 88 mm tank gun
KwK 38(t): German designation of Skoda A7, used on the Panzer 38(t)