Hi Ivan,
very awesome finding mate!!!Not common one!!!
This buckle belong to the nicknamed "FEATHERED" unmarked logo design.
Just for reference on left facing topic: YELLOW12 in a very spectacular relic finding had discovered the producer 'bout the three last buckles (before the 2 LEFT facing roundels just below): producer is Hugo Schneider AG(OSANG) you can find the post on buckle forum
Cheers
Andrea
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