2 M. Reddish carmine, centric cancellation single circle postmark \"CONSTANTINOPEL 3 26 / 4 00\", minimal irregular perforation, otherwise pristine, nice strike of the on this stamp extremely rarely stamp, from the only a few examples registered are, photo expertize Steuer BPP (2021) : \"the on this interior duty stamp extremely scarce strike of the in Constantinopel 3 ( = PERA) used town postmark shows all features of an authentic and date-appropriate cancellation. \", Steuer unpriced