Germany: Premium airmail labels

Today i received a full original sheet of Premium airmail labels from Germany. Sheet has 10 self-adhesive labels.
I've seen them only once on the envelopes coming from Germany. If there is anyone knows more about them
(release date and purpose of use) let me to know or leave a comment.

Year: ?, Self-adhesive, Günter Mair's catalogue no: - FRG-A-?, imperforated, sheets of 10(1x10),

glossy, bright dark blue/dark red/white, ref.: 912-687-000.