Very early – have not been able to ID or date because I have not found any books or sites with information on this material.
My understanding is that when one donated money to the building of Israel, these stamps were gifts – ostensibly to add to your envelopes to show your solidarity with Israel’s efforts to stay alive in these early days. Note the emphasis on planting trees, cultivating food (under guard), clearing ground and building homes. Powerful icons still very much alive today.
Sheet is 5.5 x 7 inches.
Overall Condition is Mint!