Czechoslovakia: First airmail labels

Here are the first airmail labels from Czechoslovakia. Used for different flights from Prague. Very rare!

Year: 12.1920, Gummed. Günter Mair's catalogue no: - CSR-A-1, perforated 11 or 11½ , 
sheets of 100(4x25), orange-red/grey-blue/white, 6******

  




Year: 12.1920, Gummed. Günter Mair's catalogue no: - CSR-A-2, perforated 11 or 11½ , 
sheets of 100(4x25), orange-red/grey-blue/white, 6******

Year: 12.1920, Gummed. Günter Mair's catalogue no: - CSR-A-3, perforated 11 or 11½ , 
sheets of 100(4x25), orange-red/light grey-blue or grey-blue/white, 6******

 
Year: 12.1920, Gummed. Günter Mair's catalogue no: - CSR-A-4, perforated 11 or 11½ , 
sheets of 100(4x25), orange-red/light grey-blue/white, 6******