This is an antique Japanese military sake cup, decorated with a pair of flags, a star, and the words "40th Infantry Regiment Commemoration" and the soldier's name Uchida on the back. The cup has a scalloped shape and there are kiris indented into the cup at 3 spots - 12, 4, and 8 o'clock. I tried showing it in the photo but it's difficult to see.

Condition: Mint

Size: 2.5" across