I thought I would show a seldom seen green piped NCO peaked cap (Schirmmutze) as worn by the Luftpolizei after their changeover from green piped Polizei uniforms to green piped Luftwaffe uniforms circa 1933. These policemen, also called Flugpolizeibeamter or Flugpolizist, were responsible for airport security as well as movement of aircraft on the ground. They are the men in Luftwaffe uniforms that are seen wearing a gorget around their neck and signaling aircraft on the ground with hand held traffic control paddles. They also flew police aircraft in support of Polizei ground operations. A good reference is Schilling & Rettinghaus, "Die Gescichte der Luftpolizei" in the Flugzeug Dokumentation series (Vol.3).
This cap has a light green Schutzpolizei piping that was also worn by some Administrative/Specialty personnel so it is difficult to tell these apart except the Luft. Sonderfuhrer style cap piping was supposed to be a bit darker green. The cap is a nice saddle shape peaked cap made in the standard Luftwaffe style with a black leather chin strap and bound visor. It has standard aluminum Luftwaffe NCO insignia and a black ribbed band. The interior is the typical orange oil cloth generally found in enlisted peaked caps.