1945-1951 Japan WWII Allied Military Currency 10 Sen "B Yen" Note P# 63 Grades Choice AU/BU Slider. "B yen" was a colloquial term used to refer to a form of military scrip used in post-war US-Occupied Okinawa from 1946 to 1948. Officially, it was called B type military scrip. The B yen bills were of a blue or green color, and came in eight different denominations. Though the rest of Occupied Japan continued to use regular Japanese yen throughout occupation, military scrip was introduced in Okinawa because, even at that time, the US military government intended to continue occupation of Okinawa long after ending it in the Home Islands. Steps were taken to prevent inflation which would have resulted from the illegal influx of regular yen from the Home Islands. Once the economy in Okinawa was considered stable enough, the B yen was done away with, and the US dollar brought into use.