60 penny on 40 C. Airmail stamp, overprint type I on white paper, corner margin block of four lower left with date of printing \"G 1001 31\", mint never hinged, in the margin of sheet diagonally crease and lower perforation prefolded - apart from that impeccable mint never hinged condition, expertise Nagler VP (2022) : \"genuine and immaculate\", Michel 1.800.- plus