US Army doctrine of WWII dictated that tanks were not to be fought with tanks. Instead, enemy tanks were to be countered with tank destroyers. The M10 Tank Destroyer was the most successful of these specialized vehicles and was used to make openings for Allied tanks to support infantry and exploit these gaps in the enemies' lines. The M10 featured a 3-inch gun (76.2mm) on a fully traversing turret on a chassis based on the M4 Sherman. It's pictured here with its main weapon buttoned down and facing backwards. 4,993 M10s were produced at the GM Tank Arsenal during World War II, starting in September 1942, and about a thousand M10A1s were built by Ford. The M10 was powered by twin GM 6-71 diesel engines, capable of road speeds of 25 mph. For antiaircraft defense the M10 was armed with a .50 caliber machine gun. The open topped turret, designed to save weight and accomodate the tank destroyer's large main gun was a disadvantage that made the crew vulnerable to artillery, mortar fire and close assault by infantry. The crew of five also carried Thompson machine guns and grenades. The 347th Ordnance Depot Company was in direct support of the Third Army's armored divisions in the Spring of 1945 and the M10 was one of the fighting vehicles that they serviced.
Doyle, David. U.S. Military Vehicles Field Guide. Iola, WI: KP Books, 2005.
"M-10 Tank Destroyer." Olive-Drab.com. May 22, 2008. Oct. 20, 2010. http://www.olive-drab.com/idphoto/id_photos_m10td.php