This is a Bakelite NCO's whistle is decent to good condition. This is the "text book" style whistle that collectors look for though many versions were used. This style of whistle has been produced for a very very long time in Germany and is still made today (although in modern materials). The Bakelite ones were produced from the 1920's-60's with minor variations mostly depending on manufacturer. This could be original, pre-war or early post-war. There is no way for anyone to ever know for sure. Very nice example for your collection or impression. It measures about 2 1/2" long.