China, Republic: Airmail labels 2

More Chinese labels.

Year: 1938, Ungummed, Günter Mair's catalogue no: - CHN-A-5a, rouletted, sheets of 40(4x10), "PAR AVION": 28mm , black/blue, 3***

Year: 1939, Ungummed, Günter Mair's catalogue no: - CHN-A-6, rouletted, sheets of 40(4x10), "PAR AVION": 28.5mm , issued at Pecking,  black/blue-grey or light blue-grey, 3***

Year: 1941, Ungummed, Günter Mair's catalogue no: - CHN-A-8, imperforated, sheets of 40(4x10), "PAR AVION": 28mm , issued at Chengdu, black/light grey-blue, 4****

Year: ?, Ungummed, Günter Mair's catalogue no: - CHN-A-?, rouletted, sheets of 40(4x10), "PAR AVION": 28mm , black/light greenish-blue, 3***