Military Payment Certificates (MPC) were substitute currency issued to U.S. service members stationed overseas to discourage black market trading in U.S. dollars. This one-dollar note from Series 681, introduced in 1969 during the Vietnam War, features a portrait of a military jet pilot in full flight gear. MPC notes were used exclusively on U.S. military installations and were periodically replaced without warning to further curb currency speculation. Project: 219092