Issue n° 12 - 1967
Number of countries : 19
Debuting countries : none
Returning countries : none
Withdrawing countries : none
Common design : three cogwheels. The central cogwheel has the CEPT logo in his center and 22 teeth, one tooth for each 1967 members of CEPT.
Countries using their own design : San Marino (Map of Europe) - Liechtenstein (their design is slighly different, their coghwheel has only 10 teeth)
Designer : Oscar Bonnevalle (Belgium)
Note : Most stamps issued in late April and early May.