20l sky-blue in pair on cover canc. "ΣΚΙΑΘΟΣ*5.ΙΟΥΝ.73", double control numbers (Kound. 47.1.c), arr. "ΧΑΛΚΙΣ*10.ΙΟΥΝ.73". Skiathos P.O. not mentioned in Koundouros study under 47.1.c case. Very fine and rare on cover. (Hellas 35aNoI).