Photos: A century of tanks

The M7B2 105mm Howitzer motor carriage was a World War II-era U.S. Army contraption also known as "Priest." It carried a crew of seven and had both an M2A1 105mm rifled Howitzer and an M2 HB .50 caliber heavy machine gun. It weighed 50,600 pounds, could hold 175 gallons of gas, and had a top speed of 25 mph and a range of 120 miles.

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Photo by Daniel Terdiman/CNET News.com