Designed to provide a higher rate of fire than an earlier design, the 2cm Flak 38 proved to be a mainstay of the German light anti-aircraft defences in WWII. Entering service in early 1940 this Flak saw service in all major theatres. With a small calibre it was primarily used against low flying aircraft, but was also effective against ground targets including soft-skinned vehicles. The Sd.Ah.51 trailer was used when towing the gun, behind a light truck, such as the Krupp Protze or Opel Blitz, or a half-track such as the Mauliter. The Flak 38 was also mounted on permanent positions such as Flak towers and coastal fortifications; boats; railway wagons, and military vehicles, such as the Sd.Kfz 10/5 half-track.