Specimen 1941 Sun Yat-sen set of 16 values overprinted "SPECIMEN" in red and with security punch hole, lower margin blocks of four, fine, unmounted mint. Only a maximun if 250 sets can exist. S.G. 583-598, Chan 496-511. Also 1908 revenue 20ca., 100ca. and 1000ca overprinted "SPECIMEN", with punch hole, in horizontal pairs. Photo