This Vatican City postage due stamp, issued in 1929, bears the denomination of 20 centesimi and features the classic emblem of the Holy See — the crossed keys of St. Peter surmounted by the Papal Tiara. Designed by C. Mezzana, the intricate engraving and fine rope border symbolize papal authority and the unity of the Church. The word “Segnatasse” denotes its purpose for indicating postage due. This early issue belongs to the first definitive Poste Vaticane postage due series, highly prized for its crisp typography and ecclesiastical symbolism.