6 Pfg Hitler bright blue violet with double overprint, of it one inverted, block of four on piece, centric cancellation "DÖBELN 1 c 20.7.45", in perfect condition, scarce and decorative unit, twice signed storm and new photo expertize Kunz BPP (2018) "the block of four. . . Is genuine and in perfect quality. The cancellation postmark. . . Is date-appropriate. ", by Michel unpriced