Military Payment Certificates (MPC) were a form of substitute currency issued to U.S. service members stationed overseas, designed to prevent the accumulation of U.S. dollars on local black markets. This ten-cent note is from Series 681, introduced in 1969 during the Vietnam War, and features a vignette of a U.S. Navy submarine. MPC notes like this one were periodically recalled and replaced without notice to further disrupt currency speculation. Project: 219092