10 Pfg on 30 Pfg Germania with overprint \"Gdansk\", Michel-no. 5 with new overprinted value as proof for Michel-no. 17, unused block of four from lower margin of the sheet, the overprint colour the numerals is top left green, top right and by the lower stamps orange red, in this kind is the block of four a very scarce unit, unsigned, photo expertize Gruber BPP (2016) : \"the stamps are genuine and in perfect quality. \", Michel in this kind not listed rarity!