The «Haunebu II» PVC patch

Haunebu (also spelled Hauneburg-Geräte, Reichsflugscheiben, RFZ, etc.) is a name given to a class of supposed flying-disc or UFO-type aircraft that conspiracy theories allege were developed by Germany during or just after WWII. 

The concept is closely tied to the broader mythos of “NS UFOs” or “German flying saucers” — a speculative, mystical or pseudoscientific narrative rather than accepted historical technology. 

In the German context, Reichsflugscheibe (“Imperial flying disc”) is sometimes used as a generic label for these alleged crafts