unused 1891 (May) 2c. on 24c. green (S.G. Type 17), a very fine example with the error "CENST" from [28] in each sheet from the 1st printing giving a possible total of 108 examples; some clipped perfs as always but a much above average example. R.P.S. Certificate (1968). S.G. 17a, #450. Photo