German antiaircraft gun  50 mm Flak 41
U.S. Army
1945-08-02
Catalog of enemy ordnance (<a rel="nofollow" class="external free" href="https://archive.org/stream/CatalogOfEnemyOrdnanceMateriel#page/n55/mode/2up">https://archive.org/stream/CatalogOfEnemyOrdnanceMateriel#page/n55/mode/2up</a>)