GJ.171b, with DOUBLE OVERPRINT variety, MNH, signed by Victor Kneitschel on back, VF quality, rare! (Image)

GJ.360, 1915 Plowman 12c. on Italian paper with horizontal honeycomb wmk, originally with "M.I." overprint but with a second "I" added, typographed, mint with tiny hinge mark, excellent quality, extremely rare, signed by Victor Kneitschel on back! (Image)

GJ.483a, INVERTED OVERPRINT variety, only known used, excellent quality, extremely rare, signed by Victor Kneitschel! (Image)

GJ.530, 1920 2c. San Martín with multiple suns wmk, perf 13½, M.O.P. overprint, mint lightly hinged, VF quality, very rare! (Image)

GJ.684CZ, with label at left, rare! (Image)