50 Kop. special stamp "sport badge GTO" with hand stamp overprint "Eesti post", used "ELVA EESTI B . . . . 41", in the perforation area in of the left upper corner brownish discoloration - otherwise faultless condition, issued only 65. copies, expertized Krischke BPP and Pickenpack as well new photo expertize Nagler VP (2018), Michel 4.000.- - very rare stamp!