US: Airmail labels

Here are some very rare airmail labels from USA.

Year: 1928, Ungmmed. Günter Mair's catalogue no: - USA-C-12a, perforated 12 ½ , sheets of 25 labels 12a + 5 labels 12b, plane in red, red/blue/white, 6******

Year: 1928, Ungummed, Günter Mair's catalogue no: - USA-C-12b, perforated 12 ½ , sheets of 25 labels 12a + 5 labels 12b, colours inverted, plane in blue, blue/red/white, 6******

Year: 1928, Gummed. Günter Mair's catalogue no: - USA-C-19, imperforated, black-blue/white, 
5*****

Year: approx.1935, Gummed. Günter Mair's catalogue no: - USA-C-41, imperforated, size: 101x53mm, blue/red/white, 5*****

Finland: Airmail labels 4

Here is i nice Christmas issue labels from Finland.

Year: 2012, Self-adhesive, Günter Mair's catalogue no: - FIN-1-?, imperforated, sheets of 10 stamps+10 labels, blue/white/red,

Germany, German Reich: Rocket- mail labels 3

Here are couple more rare airmail labels from Germany intended for rocket-mail.

Year: 6.1934, Gummed. Günter Mair's catalogue no: - GER-C-23b, imperforated, V strips of 4, intended for rocket-mail, issued by G.Zucker, engineer at Hasselfelde,black/light yellow, 5*****

Year: approx.1934, Gummed. Günter Mair's catalogue no: - GER-C-?, imperforated, intended for rocket-mail, misprint: "AEROTOREEDO", issued by G.Zucker, engineer at Hasselfelde, black/light greenish blue, 6******