20l sky-blue (pos.21), "02" on control number with "0" inverted (Kound. 42.6) on entire letter canc. "ΚΑΛΑΜΑΙ*21.ΑΥΓ.70", arr. "ΠΑΤΡΑΙ*24.ΑΥΓ.70". Very fine and rare on cover. (Hellas 31bNdII).