☆Now decluttering☆ I found these while organizing my parents' house. They are imitation stamps. They cannot be used as postage stamps. It seems they were issued to commemorate the stamp exhibition held from April 7th to 11th, 1974. Due to long-term storage, the back side has slightly discolored. Please confirm. When shipping, I will fold them from the 3-column section (see photo 3) and take waterproof measures before shipping ( ˙˘˙ )