Sarawak, British Malaya: Airmail labels 2

My second airmail label from Sarawak.

Year: 1931, Ungummed. Günter Mair's catalogue no: - SWK-A-2, imperforated, sheets, 
"BY AIRMAIL: 41.5mm", black/light grey-blue, 5*****

Sarawak, British Malaya: Airmail labels

Here is a first airmail label from Sarawak.

Year: 1930, Ungummed. Günter Mair's catalogue no: - SWK-A-1, imperforated, sheets, 
"BY AIRMAIL: 40.5mm"(not 40mm as in catalog), black/light grey-blue, 5*****