SD:FlaK 38 20mm

 is a German Anti-air unit.

Overview
Flugabwehrkanone 38 was an update of the 2 cm Flak 30 produced by Rheinmetall. The design was based on the Swiss C/30 autocannon, which was in turn derived from Swiss Solothurn ST-5, which fired one of the most powerful 20 mm rounds in the world. The autocannon distinguished itself in the Spanish Civil War, leading to the aforementioned Flak 30 being developed specifically for the Heer.

The Flak 38 20 mm autocannon was an upgrade addressing the most common problems of the Flak 30: Increasing its rate of fire to 220 RPM from 120 and introducing a new mount that allowed for quickly setting the gun up and breaking it down. It entered service with the Heer and Kriegsmarine in 1939.

A total of over 144,000 units were produced between 1934 and 1945, making it one of the most widely produced weapons in the German arsenal. It was mounted on a variety of platforms, including stationary emplacements and self-propelled mounts, and available in a quadruple form: The Flakvierling 38. Although intended for use against aircraft, it was a powerful heavy machine gun, comparable in role to the Browning M2.

Strategy
The FlaK 38 20mm is a weak AA gun and must be used in large numbers to even repel enemy aircraft. It can also be used as an anti-infantry weapon, given its range and decent HE.