The U.S. Military M274 Truck, Platform, Utility, 1/2 Ton, 4x4 or "Carrier, Light Weapons, Infantry, 1/2 ton, 4x4," also known as the "Mule," "Military Mule", or "Mechanical Mule," is a 4-wheel drive, gasoline-powered truck/tractor type vehicle that can carry up to 1/2 ton off-road. There were 11,240 Mules produced between 1956-1970, when production ceased. They were used throughout as platforms for various weapons systems and for carrying men, supplies, and weaponry/ammunition during the Vietnam War and in other U.S. military operations until the 1980s. The M274 Mules were often outfitted with a wide array of weaponry, especially in the Vietnam War. They could be modified to carry virtually any type of conventional weapon that could be mounted on a truck. All Mules had three-speed manual, non-synchromesh transmissions with two-speed transfer cases, and were four-wheel drive vehicles. The lower speeds and high power (17 hp) of the Mule made it a versatile off-road vehicle. It could climb over logs, go up steep slopes, and cross rivers in first gear.