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The M50 Ontos (Greek for "thing") was an American light armored tracked anti-tank vehicle developed in the 1950s as a fast tank killer for airborne forces.
It mounted six M40 106 mm rocket launchers as its main armament, which could be fired in rapid succession against single targets to guarantee a kill.
The M50 was produced in limited numbers for the U.S. Marines after the U.S. Army lost interest in the project.
The Marine Corps consistently reported excellent results when they used the Ontos for direct fire support against enemy infantry in numerous battles and operations during the Vietnam War.
The appearance of the M50 Ontos was sometimes enough to make the Vietnamese forces break and run, and anecdotal accounts describe these enemies fleeing occupied buildings when a single spotting round fired from the M50 entered a window.
The American stock of Ontos was largely expended towards the end of the conflict and the remaining vehicles were finally removed from active service in 1969.
The Ontos inspired the design of the Monster Destroid mecha from the MACROSS science fiction series from the 1980s.