Sweden: Full sheet of first flight labels.

Here is a very nice and attractive item from Sweden. It's full sheet of 20 airmail labels issued in 1944. These labels were used for the first postal flights between Swedish cities. All 20 labels are different. Also it's not listed in
Günter Mair's catalogue. All labels has full gum on them. I've never seen the labels like these. It could be a quite rare item.

Year: 1944 approx, gummed.