Oman: Airmail labels 2

Here are more airmail labels from Oman. A block of 4 and and couple of single labels.

Year: approx.1975, Gummed. Günter Mair's catalogue no: - OMN-A-2b, rouletted (wide steps), 
sheets, blue/white, 2**

Year: 1989, Gummed. Günter Mair's catalogue no: - OMN-A-3, rouletted (narrow steps), 
sheets of 50(5x10), light blue/white, 1*

Year: ?, Gummed. Günter Mair's catalogue no: - OMN-A-4?, rouletted (wide steps), sheets,
grey-blue/white,

Oman: Airmail labels

This is a nice old label from the Sultanate of Oman. Oman is an Arab country in southwest Asia on the southeast coast of the Arabian Peninsula. The airmail label has the same design as Oman's flag.

Year: approx.1970, Gummed. Günter Mair's catalogue no: -  OMN-A-1b, perforated 11, sheets,
violet-blue/red/green/white, 2**