German NSDAP Party Member Badge 'M1/77'

In a very good condition a German NSDAP (Nationalsozialistische Deutsche Arbeiterpartei) Party Membership Badge (or Mitglied Parteiabzeichen) The early enamel badge comes with maker marking RZM M1/77 on the reverse side and has a functional needle and catch. RZM M1/77 indicates production by Foerster & Barth-from Pforzheim.