Bank of England, Cyril Patrick Mahon (1925-1929), 1, ND (1928), serial number H01 777777, green and blue-mauve, ornate crowned vignette of Britannia at left, value at right, reverse green, value at left and right (EPM B212, Pick 363a), the first prefix for the last series and a highly unusual solid number, in PMG holder 35 Choice Very Fine and rare