War bonds were a form of savings bond used in the United States and Canada to help fund World War I and World War II. They were also a measure to manage inflation by removing money from the economy heated up by the war efforts.
During World War II, in the U.S. there was a promotional cardboard container with slots for quarters. There were 75 slots for $18.75 in quarters. When it was full, one turned it in at the postoffice for a $25 war bond which matured in 10 years.
