The 5 cm KwK 38 L/42 (5 cm Kampfwagenkanone 38 L/42) was a German 50 mm calibre cannon used as the main armament of variants of the German SdKfz.141 Panzerkampfwagen III medium tank during the Second World War. There was no towed anti-tank gun equivalent.
Average penetration performance established against rolled homogenous steel armour plate laid back at 30° from the vertical.