 Complete the following phrase:  The first M2s were fielded in 1941, and would be used in the Philippines, North Africa, and Europe by the U.S. Army, and around the Pacific by the Marines. About 800 M2 and M9 half-tracks were sent to the Soviet Union. Many remaining vehicles initially destined for Lend-Lease were transferred to other U.S. allies, primarily in South America. These vehicles often received a number of upgrades designed at extending service life. The Nicaraguan National Guard received 10 M2s in 1942, which saw heavy action during the 1978-79 