Rare Roter Frontkämpferbund communist organization buckle made from brass. Used condition. The Roter Frontkämpferbund ("Alliance of Red Front-Fighters"), usually called Rotfrontkämpferbund, abbreviated RFB, was a German paramilitary organization affiliated with the Communist Party of Germany during the Weimar Republic (KPD). It was officially a non-partisan and legally registered association. The organisation was banned as extremist by the governing social democrats in 1929.