3rd Reich Die Bayerische-Ostmark Ruft 1937 Porzellan abzeichen

In an excellent condition a porcelain badge The Bavarian-Ostmark calls 1937 Frontside: Large eagle with Swastika holding a blue colored shield. Die Bayer.Ostmark Ruft. With sight of the Ostamrk. Gautag 1937. Backside: Safety pin. Maker marked F. Thomas from Marktredwitz