The M4 Sherman was the primary tank of the United States and used it during World War II. M4 Medium tank production exceeded 50,000 units and its chassis served the basis for numerous other armored vehicles such as tank destroyers, tank retrievers and self-propelled artillery. The M4 was named the Sherman in the United Kingdom, after Union General William Tecumseh Sherman. The M4 medium tank was used by the US until the end of the Korean War and many nations continued to use the tank in the late 20th century and was used in both training and combat roles. In October 1942, the first Shermans saw action with the British Army at the Second Battle of El Alamein. As the North Africa campaign progressed, M4s and M4A1s replaced the older M3 Lee in most American armor formations. When the Sherman first entered service, it was far more superior to the German tanks it encountered in North Africa and remained at least on par with the medium Panzer IV series throughout the war.