Italian pneumatic mail stamps
In Italy they didn't use specially made envelopes and postcards with pre-printed postage stamps, like in Germany, France and other countries. They had beside the stamps for the regular mail, separate stamps for the transport by Pneumatic Mail!
Series 1 - Stamps with the picture of King Victor Emanuel III of Italy
Series 2 - Stamps with pictures of Dante Alighieri and Galileo Galilei
Series 3 - Stamps with the picture of a unknown person or character
King Victor Emanuel III of Italy (1869 - 1947)
Picture of Dante Alighieri (1265 - 1321)
Picture of Galileo Galilei (1564 - 1642) Painting of Justus Sustermans (1597 - 1681)