German WWII Air Raid Siren- Just got this out of Europe, it is a combination of bakelite and steel. This is a hand held crank version which probably had a tripod at one time. The diameter of the bell is 7 ½ inches across. The hand crank does work. One of the steel attachments is broken. It does work, as I am sure you will find out. It is maker marked and dated 1938. There are also markings on the bakelite handle. As found condition.